The Brazilian Portuguese vowel inventory differs based on stress level. In primary stressed syllables, there are seven vowels /a, ɛ, e, i, u, o, ɔ/. In most varieties of Brazilian Portguese, the mid vowel height distinction (/ɛ/ vs. /e/ and /ɔ/ vs. /o/) is neutralized in favor of the upper-mid vowel ([e, o]) in unstressed pretonic syllables, reducing the inventory to five vowels (Câmara 1970a; Bisol & Veloso 2016; Rodrigues & da Hora 2016). For example, the lower-mid vowel in [ˈpɛdɾa] (‘stone’) becomes upper-mid in a suffixed word [peˈdɾ-ejɾu] (‘mason’), when primary stress shifts off it.1 In some Northern and Northeastern varieties, the result of mid vowel height neutralization is instead lower-mid vowels (Schwindt 2013; Bisol & Veloso 2016; Santana 2019). The current study excludes speakers from these regions. Finally, final unstressed mid and high vowels neutralize to [i, u] in most varieties, further reducing the inventory in these positions ([a, i, u]) (Câmara 1970a; Major 1985; Mateus & d’Andrade 2000; Barbosa & Albano 2004; Crosswhite 2004).

Primary stress in Brazilian Portuguese falls within a trisyllabic window at the right edge of the word and can be penultimate ([izoˈlada] ‘isolated’), antepenultimate ([ˈvalida] ‘valid’), or final ([maɾakuˈʒa] ‘passionfruit’). Many scholars argue that primary stress assignment is weight-sensitive for non-verbs (e.g. Bisol 2010; Wetzels 2007; Garcia 2017). Penultimate stress is considered default (Câmara 1970b; Wetzels 2007): when all syllables are light, stress is almost always penultimate (Garcia 2017). Garcia (2017) argues that antepenultimate and final stress can be partially predicted by the shapes of the final three syllables. However, stress can also be contrastive, indicating that it is lexically marked at least in some cases (e.g. [ˈsabja] ‘wise’ vs. [sa ˈbja] ‘kind of bird’ vs. [saˈbi.a] ‘3SG knew’).

Secondary stress assignment depends on the number of pretonic syllables in morphologically simple words. Words with an even number of pretonic syllables have alternating, binary secondary stress ([ˌpĩdaˌmoɲãˈgaba] ‘place name’) (Lee 2002). Words with an odd number of pretonic syllables either have alternating, binary secondary stress ([aˌbakaˈ∫i] ‘pineapple’) or initial prominance ([ˌabakaˈ∫i]) (Collischonn 1994). In most morphologically complex words, regular secondary stress is assigned as in morphologically simple words (1)–(2) (Collischonn 1994).

Many theories of metrical stress are designed to capture secondary stress assignment, but experimental research often fails to find supporting acoustic evidence of this stress. Studies of languages as diverse as Spanish (Romance; Prieto & van Santen 1996; Díaz Campos 2000; Hualde & Nadeau 2014), Polish (Slavic; Newlin-Lukowicz 2012), Pitjan-tjatjara (Pama-Nyungan; Tabain et al. 2014), and Indonesian (Polynesian; Adisamito-Smith & Cohn 1996) do not find robust acoustic evidence to verify impressionistic reports of secondary stress. In Brazilian Portuguese, the evidence is also limited and inconsistent in both production (Gama Rossi 1998; Moraes 2003; Arantes & Barbosa 2006) and perception (Moraes 2003; Keller 2004). My production study also finds no evidence of regularly assigned, rhythmic secondary stress and I do not discuss it further.

In Brazilian Portuguese, most suffixes are normal suffixes like -eiro, -ista, -mento, -oso, – (i)dade. They integrate prosodically with the base: primary stress is assigned to the entire word as a single unit, falling within the final trisyllabic stress window. Secondary stress also applies to the word as a whole (see (1)–(2)).

Special suffixes are a closed class that consists of the diminutive -inho/-zinho, the superlative -íssimo, and the adverbial suffix -mente.2 The form of the diminutive is determined mostly by the phonological shape of the base.3 -zinho typically attaches to words with final stress ([kaˈʒu], [kaˌʒu-ˈzĩɲu]) or antepenultimate stress ([esˈkãdalu], [esˌkãdalu-ˈzĩɲu]), but can also attach to words with penultimate stress ([aˈmigu], [aˌmigu-ˈzĩɲu]). With -zinho, the theme vowel is always maintained (underlined) ([amig-u-ˈzĩɲu]). -inho and -íssimo attach to bases with penultimate or antepenultimate stress, and the theme vowel deletes ([kaˈlad-a], [kaˌlaˈdʒ-ĩɲa]; [ˈvalid-a], [ˌvaliˈdʒ-isima]). -mente attaches to adjectives (which have penultimate or antepenultimate stress) and maintains the theme vowel ([kaˌlad-a-ˈmẽt∫i]). The diminutives also differ from each other in another respect: when the theme vowel mismatches with the gender of the word, -inho maintains the theme vowel of the base, while -zinho takes the theme vowel of the gender, regardless of the base theme vowel. For example, a masculine word like o problem-a (‘the problem’) has a masculine determiner /o/, but /a/ as the theme vowel (instead of canonical masculine /o/). The -inho diminutive maintains the theme vowel of the base (o problem-inh-a), while -zinho takes the canonical theme vowel corresponding to the gender of the word (o problem-a-zinh-o). This suggests some difference in attachment. See Lee (2013), Armelin (2014) and Ulrich (2016) for more discussion.

The special suffixes are often analyzed as independent prosodic words that receive stress and undergo reduction separately from their bases (e.g. Brakel 1981; Moreno 1997; Vigário 2003; Bachrach & Wagner 2007; Lee 2013; Schwindt 2013; Ulrich 2016; Guzzo 2018; Ulrich & Schwindt 2018). Similar arguments have been made for Italian (Vogel & Scalise 1982) and Spanish (Harris 1983; Roca 1986; Crowhurst 1992). While the three languages have many similarities, Spanish and Portuguese adverbials differ from Italian adverbials in several informative ways (see Section 3.4).

In most analyses of Portuguese, the special suffixes form compound prosodic word structures (Menuzzi 1993; Moreno 1997; Lee 2002; Vigário 2003; Quadros & Schwindt 2008; Schwindt 2013; Toneli 2014; Guzzo 2018). That is, both the base ([kaˈlada]) and the suffix ([-ˈmẽt∫i]) are prosodic words nested within a larger prosodic word: [[kaˈlada]ω[ˈmẽt∫i]ω]ω. This is illustrated in (5).

Guzzo (2018) argues that special suffix words are prosodized recursively within the prosodic word domain, resulting in a larger prosodic word to which post-lexical processes—like regular secondary stress—can apply.4 Special suffix words differ from word-word compounds like guarda-chuva (‘umbrella,’ lit. ‘keep-rain’; Guzzo 2018), which are not prosodized recursively within the prosodic word domain, and have slightly different stress assignment. However, in Guzzo’s (2018) account, both special suffix words and word-word compounds consist of multiple prosodic words. Maintenance of vowel quality in the base follows naturally, since stress and vowel reduction apply to each part independently.

The most straightforward phonological argument that special suffix words contain an independent prosodic word base is vowel height (F1) in pretonic and base-final vowels. As discussed in Section 2.2, mid vowel height contrasts are not neutralized in special suffix words, if the vowel is stressed in the independent base. Additionally, base-final vowels in special suffix words undergo extreme reduction as if they were word-final. Portuguese has different degrees of vowel reduction: word-final vowel reduction is extreme, while word-internal unstressed vowel reduction is less so (Crosswhite 2004). For example, word-final /o/ in /amigo/ reduces to [u] ([aˈmigu]), and the extreme reduction is maintained in the diminutive ([aˌ migu-ˈzĩɲu]). This suggests a prosodic word boundary after the base in the special suffix word (Toneli 2014; Ulrich 2016; Guzzo 2018).

Scholars generally agree that -zinho and -mente attach to independent prosodic word bases and are independent prosodic words themselves (Menuzzi 1993; Moreno 1997; Lee 2002; Vigário 2003; Quadros & Schwindt 2008; Schwindt 2013; Toneli 2014; Guzzo 2018). There is less agreement about the -inho form of the diminutive and -íssimo, which some authors argue to behave like normal suffixes with regard to secondary stress (Menuzzi 1993; Collischonn 1994; Moreno 1997; Lee 1999; 2013). This appears to hold of European Portuguese (Villalva & Gonçalves 2016). However, all four suffixes block mid vowel height neutralization in Brazilian Portuguese (Quadros & Schwindt 2008; Ulrich 2016; Ulrich & Schwindt 2018).

To preview, my analysis departs from analyses that treat all special suffix words as nested prosodic word compounds. In my analysis, all bases are independent prosodic words, but -mente is the only suffix that is itself a prosodic word. Diminutive and superlative suffixes attach to a prosodic word base, but are not themselves independent prosodic words.

Words with special suffixes contain an independent prosodic word base while normal suffixes form a single phonological word with their bases. Can we account for this difference in a principled way? Is there a morphological characteristic that groups the special suffixes together, to the exclusion of normal suffixes? In frameworks like Distributed Morphology, morphological structure and phonological structure are linked: prosodification cycles are defined by syntactic domains. Indeed, the special suffixes differ morphologically from normal suffixes in place and manner of attachment.

I briefly present the Distributed Morphology framework (Halle & Marantz 1993) (Section 3.2.1) and discuss diagnostics for place and manner of attachment (Section 3.2.2), before sketching the analysis of diminutives/superlatives and adverbial -mente (Sections 3.3 and 3.4). DM provides a principled way of explaining the prosodic output. It is not inconsistent with prosodic phonology, but comes in at an earlier step to connect structure to prosody.

In a DM framework, place and manner of attachment affect which chunks of material are spelled out together. For manner, I follow Villalva (1994) and Bachrach & Wagner (2007) in treating diminutives in Brazilian Portuguese as morphological modifiers. For Bachrach & Wagner (2007), diminutives attach as modifiers outside the categorizing head of the base (11). Normal suffixes, in contrast, are the realization of the categorizing head (10). This corresponds with category-changing behavior: diminutives and superlatives do not affect the category of their bases, while normal suffixes do. The trees in (10) and (11) are adapted from Bachrach & Wagner (2007).

Spell-out domains are marked in the trees. Categorizing heads trigger spell-out (Marantz 2001; Marvin 2002), sending all material in that node and its sister to phonology. Normal derivational suffixes (-ad- in (10)) attach to roots as the realization of a category-assigning head (a), which triggers spell-out of itself and its complement (√kal + -ad-). This chunk—root + normal suffix—is assigned stress as a whole because morphology feeds it to phonology as a unit. Special suffixes are different (11). The suffixes -inho/-issimo attach outside the categorizing head as modifiers, not affecting the category of the base. The base (√kal + -ad-) is sent to phonology to the exclusion of the special suffix, and undergoes phonology. The stress assigned to the base at this stage is maintained even after the suffix is added.

Recall that diminutives and superlatives can also attach outside number and gender marking (Section 3.2.2). Bachrach & Wagner (2007) allow an additional place of attachment above the first number phrase for diminutives (12), which can be extended to superlatives since they allow similar number and gender marking on the base. Like in (11), spell-out in (12) occurs at the categorizing head, sending the base to spell out separately from the special suffix.

Table (13) illustrates the cyclic interaction of phonology and morphology determined by the tree structure. The input to (13a) is a tree like (12); the input to (13b) is a tree like (10). While the roots and suffixes used in the trees differ, they are of the same structure. This derivation differs from a strictly Lexical Phonology account with level ordering. The apparent levels result from morphological structure, and the phonological results depend on how much of the word is present at specific points of the derivation.

In (13a) and (13b), ω marks phonological word chunks that are formed when categorizing heads send material to spell-out. Starting from the underlying root /kaˈfɛ/, which I assume to have lexically marked final stress, the morphology feeds the first chunk to phonology. For the normal suffix word, both the base and suffix are present, since the suffix is the first category head. For the special suffix word, only the base is present, since the suffix attaches outside this first spell-out domain. Stress is assigned to material that is present, and multiple primary stresses within a phonological word are resolved by subordinating all but the rightmost. Unstressed mid vowels neutralize and raise.7 Finally, word-level secondary stress optionally applies. The derivation ends there for the normal suffix word. For the special suffix word, the first round of phonology treats the base, which does not result in any changes. The second spell-out cycle feeds the diminutive suffix -zinho to phonology, and the same phonological processes now apply to the entire word. Primary stress is assigned at the word level and falls on the suffix. Stress on the base from the first part of the derivation is maintained due to constraints preventing modification of stress assigned in a previous cycle (Prince 1985; Pruitt 2010). This prevents mid vowel neutralization from applying. I mark maintained base stress as secondary, but whether it subordinates to primary stress is an empirical question. The final step of word-level secondary stress is optional.

I assume that default word-level primary stress (penultimate) is assigned in most cases. Diminutives and adverbials require no extra modifications, since they have penultimate stress regardless of whether stress is lexically marked or assigned as default. In compunds, primary stress always falls on the rightmost prosodic word (Vigário 2010). Superlatives require an additional assumption: stress is always antepenultimate (-íssimo) and must be lexically specified. Faithfulness to lexical stress must override default stress assignment at the word level. One could also assume that all special suffixes are lexically stressed (e.g. Vigário 2003).

I depart from previous analyses that consider all special suffix words as nested prosodic word compounds. The only necessary component to blocking mid vowel neutralization on the base is that the base must be an independent phonological word. I consider words with diminutive/superlative suffixes to consist of an independent prosodic word base and a suffix, which combine into a larger prosodic word (14). The special suffix is not a prosodic word in and of itself. Only words with -mente consist of two independent prosodic words nested within a larger one, forming a prosodic compound (15).

Note that (14) and (15) show the final prosodic structure, without saying anything about how this structure is derived. They do not imply that the special suffix selects for a prosodic word base, but rather that this structure is the result of morphologically-determined cyclic spell-out.

While diminutives and superlatives can be analyzed as modifiers, recall that adverbial -mente shares characteristics of both derivational suffixes and compounds (see Section 3.2.2). Phonologically, however, it has been analyzed as forming compound prosodic words like the other special suffixes (Section 3.1). Treating -mente as a root that forms a morphological compound creates the phonologically parallel behavior, despite morphological differences.

There is a long-standing debate in the literature about whether -mente is a derivational suffix or forms a compound. For Spanish, a compound analysis is supported by Bello (1847), Hockett (1958), Bosque (1987), Zagona (1990), and Kovacci (1999). A morphological derivation analysis is argued for in Alarcos Llorach (1970), Karlsson (1981), Miranda (1994), and Rainer (1996) (see Torner 2005 for overview of debate). For Portuguese, Rio-Torto & Ribeiro (2012) propose that -mente is a frontier case between derivation and compounding, and Basílio (1998) argues that is not derivational. I discuss Spanish and Italian in conjunction with Portuguese because much of the existing work focuses on these languages, and because their similarities and differences from Portuguese are informative.

For Spanish, Bosque (1987), Zagona (1990), and Kovacci (1999) argue that -mente forms compounds. One source of evidence is deletion (ellipsis) under coordination. -mente can scope over multiple feminine-inflected adjectives, appearing overtly only on the last one. In both Spanish and Portuguese, this is possible with -mente (16a), some prefixes (16b), and some compound structures (16c), but not with any normal suffix (16d).

However, ellipsis is not purely phonological, and thus cannot be the the only diagnostic for compound prosodic words (Vigário & Frota 2002; Vigário 2003; Guzzo 2018). If ellipsis is only allowed in phrases composed of multiple prosodic words (Guzzo 2018), then adverbials must contain multiple prosodic words. However, the same evidence cannot be used for the other special suffixes, which disallow ellipsis but are analyzed as independent prosodic words (Guzzo 2018). Ellipsis may be blocked in diminutives for semantic reasons (Vigário & Frota 2002). Containing two phonological words is necessary—but not sufficient—for ellipsis. Furthermore, some languages have similar processes where an affix scopes over a series of coordinated bases (e.g. Turkish, Kabak 2007), but this does not result in multiple prosodic words. My analysis treats -mente as an independent prosodic word that forms a phonological and morphological compound with its base, while the other special suffixes do not. This could explain why only -mente can undergo ellipsis.

Further arguments for the compound analysis of Spanish -mente are that it attaches to already-inflected adjectives (8). Derivational suffixes do not attach to inflected forms. It also attaches outside the superlative suffix, while normal suffixes cannot (Torner 2005). A final major argument is that -mente maintains stress on the base, but this argument is phonological rather than morphological. Basílio (1998) makes similar arguments for Brazilian Portuguese, focusing mostly on ellipsis under coordination and attachment to a feminine-inflected adjective.

As a counterpoint to Spanish and Brazilian Portuguese, modern Italian -mente is more clearly derivational (Masini & Scalise 2012). Modern Italian does not allow ellipsis under coordination—although Ancient Italian did. Masini & Scalise (2012) propose that the discrepancy between modern Italian on one hand, and Spanish and Ancient Italian on the other, may be that modern Italian -mente has fully grammaticalized into a derivational suffix while Spanish -mente has not. Spanish and Portuguese are similar with regard to distribution of -mente, so it is possible that the suffix is grammaticalizing in these languages (Silva et al. 2008; Duarte 2009), and that -mente words may still be morphological compounds.

I follow Basílio (1998) in analyzing -mente as a morphological compound in Brazilian Portuguese. I consider morphosyntactic compounds to consist of two roots (Harley 2009; Borer 2014). Thus, adverbials contain two independently categorized roots (√base + √–mente). Because each root is categorized, they spell out separately and receive independent stress. One reason to treat -mente as a root is diachronic: it derived from an independent lexical word. In most accounts, the Romance suffix -mente derived from Latin compounds of a feminine-inflected adjective (lent-a ‘slow-F.SG’) plus the independent noun mens (‘mind’) (Basílio 1998; Kovacci 1999; Duarte 2009; Silva et al. 2008).8 There are also striking diachronic similarities between English adverbial -ly and Romance -mente. English -ly derives from Germanic NOUN-NOUN compounds composed of *-lîkom ‘appearance, body, form’ (cognate of modern English -like) and another noun (OED 2018). For example, *mann-lîko originally meant ‘having the appearance or form of a man.’ Over time, *-lîkom reduced phonologically to -ly and changed from an independent noun to a bound adverbial suffix. Modern English has both -ly and -like, the latter of which is both an independent word and a suffix with relatively independent behavior. The independence of the suffix -like mirrors -mente: -like does not modify stress on its base (e.g. Saskátchewan, Saskátchewan-like). Other English suffixes are also argued to be compounds for similar reasons (e.g. -type, Dalton-Puffer & Plag 2001).

Objections to the compound analysis of -mente are that it is not an independent word in the language (it is bound), and -mente compounds are not identical to endocentric or exocentric compounds (Torner 2005). However, both of these objections are manageable. Bound roots are cross-linguistically common (cranmorphs, Siddiqi et al. 2014), and some affixes are treated as bound roots in languages like Halkomelem (Salish) (Wiltschko 2009), Lushootseed (Salish) (Urbanczyk 2006), and Dutch (Lowenstamm 2014; Creemers et al. 2018). While these arguments do not extend to Portuguese, the authors do draw parallels between phonological and morphological structure, as in the current study. Bound roots are not required to head their own words. Furthermore, that -mente compounds do not fit with other types of compounds may be expected if -mente is undergoing change.

The tree in (17) shows -mente as a root that forms morphological compounds.

Each root is spelled out at its respective categorizing head, and receives stress as an independent prosodic word ([kaˈlada]_ω[-ˈmẽt∫i]_ω). When the two prosodic words combine into a larger prosodic word, both stresses are maintained ([[kaˈlada]_ω[-ˈmẽt∫i]_ω]_ω). Main word stress applies to the entire word, falling on the penultimate syllable. This coincides with the stress already on the suffix ([[kaˌlada]_ω[-ˈmẽt∫i]_ω]_ω). The leftmost stress on the base likely subordinates to main word stress somewhat, but this is an empirical question. This morphological compound structure composed of two roots differs from the modification structure for diminutives and superlatives, but the phonological result is similar. -mente is both a morphological and phonological compound, while diminutives and superlatives are composed of a single prosodic word (the base) plus a suffix.

Normal and special suffixes differ in attachment, leading to different stress patterns. The special suffixes attach to a categorized root, so that the base spells out and receives stress in a previous cycle. Normal suffixes attach to bare roots, are spelled out with the base, and receive stress as a single unit. Furthermore, diminutives and superlatives are modifiers, while adverbial -mente is a root itself, forming morphological compounds containing two roots. Prosodically, diminutives and superlatives consist of a suffix attached to a prosodic word base ([[base]_ω-DIM/SUP]_ω), while adverbials consist of nested prosodic words ([[base]_ω[-mente]_ω]_ω). Despite this difference, the surface phonology is the same since the base is spelled out independently in both cases. The nested structure of -mente raises the possibility that its stress patterns differ slightly from diminutives/superlatives, and further research is needed to test this. The place and manner of attachment of the special suffixes means that the most immediate base is spelled out and stressed independently, resulting in attachment to a prosodic word; this differs from an account in which the special suffixes select for a prosodic word base.

This analysis departs from previous work that analyzes all of the special suffixes as independent prosodic words. Specifically, it differs from Bachrach & Wagner (2007) in that the special suffixes are not dominated by a categorizing head, and are therefore not independent prosodic words themselves. An analysis in which these suffixes are independent prosodic words is also possible, but the result is that diminutives and superlatives have the same compound prosodic word structure as -mente. This may also require that these suffixes be roots that are independently categorized.

An alternative analysis is that the special suffixes are lexically marked to subcategorize for a prosodic word base. Subcategorization analyses have been proposed for cases like Kaqchikel prefixes (Bennett 2018) and Serbian function words (Zec 2005), among others. However, as further discussed in Section 6, this kind of analysis misses important generalizations about the morphological similarities in place of attachment among the special suffixes in Brazilian Portuguese. A subcategorization approach relegates the coincidence of these morphological and phonological characteristics to chance.

Cross-linguistically, correlates of stress include duration, F0, intensity, vowel quality, and spectral tilt (Gordon 2011; Gordon & Roettger 2017). Stressed segments tend to be longer, louder, and are sometimes marked by pitch excursions. Many languages have segmental alternations in stressed syllables: stressed segments can undergo fortition or lengthening (Gordon 2011), while unstressed segments are often shorter and change quality, reducing the overall vowel inventory in these positions (Crosswhite 2004). Languages differ in which correlates they use for stress, but primary and non-primary stresses tend to be signaled by the same correlates within a language (Gordon 2011; Morrill 2011; Newlin-Lukowicz 2012).

In Brazilian Portuguese, the main correlate of primary stress is duration: stressed vowels are longer than unstressed ones (Major 1985; Massini-Cagliari 1992). F1 is also an important correlate because it reflects mid vowel height neutralization in unstressed syllables (Section 2.1). Secondary stress is thought to use correlates similar to primary stress, but experimental evidence for it is inconsistent and scant in Brazilian Portuguese and cross-linguistically. Secondary stress is relevant because, although special suffixes maintain some stress on the base, it is not clear whether it is produced with correlates of primary or secondary stress. The maintained stress may be a remnant of primary stress, but is likely subordinated to main word stress. Duration and F1 are the most robust correlates of stress in Brazilian Portuguese, but I also consider intensity because some experimental work on secondary stress finds that some speakers use it occasionally (Moraes 2003; Fernandes-Svartman et al. 2012; Ulrich 2016).

Despite frequent assumptions that special suffix words maintain stress on the base, there is little acoustic evidence. Several production studies find evidence of stress maintenance through vowel height (F1), duration, and intensity (Quadros & Schwindt 2008; Schwindt 2013; Ulrich 2016). However, these studies are small-scale and their experimental weaknesses undermine the results.

Ulrich (2016) is the most thorough study, analyzing production data from 5 speakers (620 words total) from southern Brazil (Porto Alegre). Her target word bases contain lower-mid vowels /ɛ, ɔ/, upper-mid vowels /e, o/, and non-mid vowels, and have either special or normal suffixes. The crucial comparisons are between pretonic vowels that are stressed in the independent base and stressed vowels in the same suffixed word. For example, the base /ˈbɔla/ has the diminutive [bɔˈlĩɲa] and a normal suffix derived word [boˈlada] (‘bundle, jackpot’). In the diminutive [bɔˈlĩɲa], her analysis compares [ɔ] that is stressed in the independent base to primary stressed [ĩ]. Her results show that pretonic vowels that are stressed in the independent base (and thus should maintain stress in special suffix words) are similar in length to primary stressed vowels in the same word ([ɔ] ≈ [ĩ]). In words with normal suffixes, like [boˈlada], the vowel stressed in the independent base is shorter than the primary stressed vowel of the same word ([o] < [a]). Intensity shows a less robust effect in the same direction. She interprets this as evidence of stress maintenance in special suffix words but not in normal suffix words.

Schwindt (2013) also carries out a small study of pretonic vowels in special and normal suffix words. Like Ulrich (2016), he compares the pretonic vowel that is stressed in the independent base to the primary stressed vowel in the same word. Pretonic base stressed vowels are longer and slightly louder than the primary stressed syllable in the same word (e.g. [bɔˈl-ĩɲa], [ɔ] > [ĩ]). These findings are not conclusive evidence of stress maintenance for several reasons. First, intensity is not a robust correlate of primary or secondary stress in Brazilian Portuguese. Second, initial syllables are often longer and have higher intensity simply because they are initial, and because target words are focused in formulaic carrier sentences.

The main confounding factor in Schwindt (2013) and Ulrich (2016) is vowel quality. The crucial comparisons are between vowels of different qualities, which differ inherently in duration and intensity. For American English, the average duration of /i, u/ is 16ms, while that of /a/ is 30ms, and mid vowels fall in between (Peterson & Lehiste 1960: 701). These are fairly large differences. In an example like [bɔˈl-ĩɲa] (Ulrich 2016: 114), the similar durations may not be due to stress. [ɔ] is inherently longer than [ĩ], but since [ĩ] receives primary stress, its duration could be similar to [ɔ] (stressed or unstressed). The fact that [ɔ] is not shorter than [ĩ]—which Ulrich interprets as stress maintenance—may be because /ɔ/ is inherently longer than [ĩ]. Another complicating factor is that -(z)inho has a nasalized vowel and -mente has a nasal vowel. Nasal vowels are longer than oral or nasalized vowels in Brazilian Portuguese (Moraes & Wetzels 1992; Medeiros 2011), so comparing them to oral vowels is problematic. Furthermore, even if pretonic [o] is shorter than primary stressed [a] in the normal suffix word [boˈlada], this may be because [o] is inherently shorter than [a]. In sum, it is not clear if the observed similarities and differences between pretonic base stressed and primary stressed vowels can truly be attributed to stress, or whether they are a byproduct of inherent properties of different vowels. Ulrich (2016: 113, fn. 55; 122) acknowledges these confounds, but the design does not allow her to avoid them.

The previous studies do not include vowel height as a correlate of stress maintenance; they assume that base stressed vowels maintain vowel height in special suffix words. Quadros & Schwindt (2008) address vowel height explicitly in a corpus study (36 interviews) and a production study. In the interviews, special suffix words maintain lower-mid vowels in the base at the highest rates (above 90% for all). The authors do not specify how maintenance of lower-mid vowel height was determined, and do not statistically analyze the difference in rate of low-mid vowel maintenance in special vs. normal suffix words (the difference was large). They also conducted a reading experiment, marking vowel quality impressionistically. Lower-mid vowels were maintained in more than 80% of special suffix words, but in less than 25% in normal suffix words. In sum, these studies provide initial experimental evidence for stress maintenance on the base of special suffix words. However, they use few speakers, few target words, and do not control for factors like vowel quality. They also do not analyze vowel height in reproducible way, assuming that stress maintenance through vowel height is a given.

The current production study addresses these gaps in laboratory work on Brazilian Portuguese stress to provide more thorough results. I use data from 11 speakers and 92 target words. The target words were designed in sets built off the same base, allowing a comparison of pretonic vowels in special suffix words to their counterparts in normal suffix words. This design, along with more thorough statistical methods, controls for vowel quality and other factors. The target words are also presented in naturalistic sentences, to minimize effects of initial prominence.

The data were analyzed using Praat (Boersma & Weenink 2018). Between 350–480 individual vowels were used from each speaker. One target word set (base: [amaˈɾɛla]) was excluded from all of the data because many speakers had difficulty with the target words. Table 1 shows the number of vowels and ratios analyzed in the models. These numbers reflect data excluded due to reading disfluencies involving the target word or the immediately surrounding context, as well as unmeasurable vowels.

The left side of Table 1 shows the total number of vowels analyzed in all words (special and normal, stressed and unstressed in the base), broken down by vowel quality. Some outliers were later removed (see Section 4.7 for details on outliers). The underlying vowel column specifies the underlying vowel quality in the base for mid vowel pairs that are said to differ allophonically, like [kafɛ-ˈzĩɲu]: [kafe-ˈtejɾa] (UR /ɛ/). For base stressed vowels, [e, o] surface as forms of base stressed /ɛ, ɔ/ in normal suffix words, while [ɛ, ɔ] surface as forms of base stressed /ɛ, ɔ/ in special suffix words. The statistical models on raw measurements contain only the base stressed vowels.

The right side of Table 1 shows the approximate number of special:normal ratios analyzed per correlate, with outliers removed (see Section 4.7 for details on outliers). The specific numbers in this table are for Duration. All stressed base /ɛ, ɔ/ surface as [ɛ, ɔ]. The ratios reported are special:normal ratios or differences, so base stressed /ɛ, ɔ/ are maintained in special suffix words and are treated as such in the analysis. The ratio/difference models include both underlyingly stressed and unstressed vowel ratios.

The verbs and target words were segmented and coded manually by the author and four undergraduate research assistants. Strict segmenting criteria were established. We segmented the pretonic and primary stressed vowels in each target word, as well as the final vowel of the preceding verb. Primary stressed vowels of the target words and final vowels of the preceding verbs were marked but not segmented carefully, because they fall outside the analysis. Each vowel was labeled for expected vowel quality, position in relation to main stress, and sentence type. Segmentation was done with the waveform and spectrogram, using the zero-crossings of the onset and offset of F2 to mark vowel edges. The beginnings of vowel-initial target words were marked at the onset of F2, but were often difficult to determine. Preceding verbs necessarily end in vowels and the boundary is often unclear ([kãta animadaˈmẽt∫i], canta animadamente ‘sings excitedly’). When there was no clear acoustic distinction between adjacent vowels, these vowels were excluded. When they could be distinguished by abrupt changes in formant structure and intensity (e.g. because there was a glottal stop or glide), the beginning of the target word was marked at the intensity increase after low intensity of the glottal stop or glide.

Nasal and rhotic codas were segmented as part of the vowel, and the entire rime was analyzed (vowel + nasal/rhotic). Nasal vowels are assumed to be followed by an underlying nasal coda (Câmara 1970a; Mateus & d’Andrade 2000; Bisol & Veloso 2016; see Medeiros 2011 for experimental evidence). For example, regardless of whether generosamente was produced as [ӡeneɾɔza-ˈmẽt∫i] or [ӡeneɾɔza-ˈmẽnt∫i], the syllable [ẽn] ∼ [ẽ] was segmented as a unit. Coda rhotics were segmented in the same way since they are realized as taps, fricatives or retroflexes [h, ɦ, ɾ, ɹ] depending on the dialect (Cristófaro Silva 1998; Cardoso et al. 2014). Including them with the vowel was the only way to maintain consistency within and across speakers. Because the ratio comparisons are within-speaker across different members of a single target word set, a syllable with a coda rhotic (modernamente, [mod ɛɾna-ˈmẽt∫i] ‘modern-ADJ’) is always compared to the same syllable in a different form of the word produced by the same speaker (modernidade [modeɾni-ˈdadӡi] ‘modernity’). Only the relative difference between the two for a given speaker matters.

A supporting analysis with raw measurements treats each individual vowel as a token, and excludes word sets whose base contains coda rhotics, nasals, and nasal vowels. Including target word sets with codas would mean comparing vowels in syllables with and without codas. Vowels in open and closed syllables differ inherently in length, which could obscure the comparison of interest between base vowels that do and do not show base stress maintenance.

For each vowel, duration, maximum intensity, and F1 (at the midpoint) were extracted via Praat script. The raw extracted data is available in the Supplementary File 2.

Working with real words means there are confounds in experiment design and in measuring base stress realization. The most important include number of vowels, clash, vowel position, stress profile of the base, and type of special suffix. These predictors are included in the statistical models in order to control for their effects.

Number of vowels and vowel position: Differences in word length could plausibly affect the ratios because of compression in longer words. It was not possible to always have the same number of vowels in the special and normal suffix word, because special suffixes are 2–3 syllables long and differ in whether the theme vowel of the base deletes. Both -inho and -mente have 2 syllables, but -mente words are longer than -inho words built off the same base. This is because the theme vowel is deleted in -inho words ([kalaˈdʒ-ĩɲa], 4 syllables) but not in -mente words ([kalada-ˈmẽt∫i], 5 syllables). Superlatives are also longer than -inho diminutives, because the suffix is longer ([kalaˈdʒ-ĩɲa], 4 syllables) vs. [kalaˈdʒ-isima], 5 syllables). While the target words were chosen to control for word length as much as possible, a vowel in an -íssimo or -mente word may actually come from a word with more syllables than its counterpart in a normal suffix word. However, if word length did affect the comparisons, it would work against the results of the current experiment. If the normal suffix word has fewer syllables than the special suffix word, then vowels from the normal suffix words could be longer simply because the word has fewer syllables. This would lead to lower ratios, undermining effects of stress maintenance on the base. Unlike using raw measurements, the ratio design makes the effects of stress maintenance visible regardless of word length.

Clash: Stress retraction due to clash could also introduce confounds. Section 2.2 describes clash in Brazilian Portuguese. Here, I only reiterate that -inho and -íssimo frequently cause clash ([kaˈlada], [kaˌlaˈdʒísima], [kaˌ ʒu ˈzĩɲu]). -zinho can also cause clash when it attaches to a final-stress base ([kaˈʒu], [kaˌʒuaĩɲu]. If stress retraction is at work in these words, it would weaken visible effects of stress maintenance on the base. Stress retraction to a preceding syllable would make the base stressed vowel shorter and quieter, making it more similar to its normal suffix word counterpart, and lowering the ratio closer to 1.

Stress profile of the base and type of special suffix: The special suffixes can attach to bases with different stress profiles. See Section 2.2 for information on which special suffixes attach to bases of which shape. In my experiment, not all special suffixes attach to all possible bases. To maintain consistent numbers of words in the sets, I had to limit the stimuli in the following way. Penultimate stress bases occur with -inho, -mente, -issimo. Antepenultimate stress bases occur with -mente or -zinho, and final stress bases occur with -zinho. No other combinations exist in the target words.

If there is stress maintenance on the base of special suffix words, vowels that are stressed in the independent base should be acoustically different in special suffix and normal suffix words, leading to high ratios and difference measures. Unstressed base vowels should be similar in both word types. Therefore, ratios and difference measures should be higher for stressed base vowels than for unstressed base vowels. Mid vowels may show larger effects than high and low vowels, since they reduce allophonically when unstressed. The models test stress maintenance by comparing stressed base vowel ratios to unstressed base vowel ratios. Evidence of stress maintenance on the base would include a significant effect of being stressed in the base, with a possible interaction with vowel quality. Specific predictions are as follows:

Linear mixed-effects regressions were run using the lme4 package (Bates et al. 2015) in R (R Core Team 2020), with the bobyqa optimizer. P-values were obtained using the lmerTest package (Kuznetsova et al. 2017).

After data extraction, outliers were dealt with in several ways: the first round caught measurement errors from Praat, and the second excluded true outliers. First, I calculated z-scores for all individual data points for Intensity and F1 (by speaker and by vowel). I hand-checked tokens with measurements more than 3 standard deviations away from the speaker’s mean for that vowel quality. Only F1 measurements that were off by over 75Hz and Intensity measurements that were off by over 1dB were manually corrected. I did not change measurements that differed from the automatically extracted ones by less than these amounts. In two cases, Praat extracted F1 measurements of over 1000Hz; these were clearly measurement errors, but measuring by hand gave the same result. These tokens were excluded. A total of 8 Intensity measurements and 25 F1 measurements were changed manually.

Then, I excluded outliers from the raw measurement and ratio/difference data sets. In the raw measurement data set, the z-score was calculated for each data point. As before, data points falling more than three standard deviations away from the speaker’s mean for the given vowel category were considered outliers. A total of 82 individual vowel outliers were removed. Of those, øø were removed from the set of stressed base vowels that was used in the models (11 for Duration; 7 for Intensity, 4 for F1). For F1, outliers were removed after vowel normalization (Section 4.7.2).

For the ratio/difference data, outliers were defined as data points falling more than three standard deviations above or below the overall mean. Ratios/differences already control for speaker-specific differences. A total of 40 outliers were removed for Duration, 30 for Intensity, and 66 for F1.

Figure 1 shows that vowels that are stressed in the base have higher special:normal ratios than those that are unstressed in the base. For example, the ratio for stressed base [ɛ] in [kafɛˈzĩɲu]:[kafeˈtejɾa] (Base: /kaˈfɛ/) is larger than that of unstressed base [o] in [modɛɾnaˈmẽt∫i]:[modɛɾniˈdadʒi] (Base: /moˈdɛɾna/). Put differently, stressed base vowels are longer in special suffix words than in normal suffix words, while unstressed base vowels are approximately the same length in both types of words. The effect is larger for mid vowels than for high and low vowels. Base stressed mid vowels differ substantially in special and normal suffix words (leading to high ratios); base stressed low and high vowels are more similar in the word types (leading to lower ratios). Individual speakers vary, but all go in the same direction (see Appendix B, Supplementary File 1, for individual results).

The final duration model (Table 4) confirms these observations. In special:normal ratios, there is a significant main effect of Stressed in Base, and a significant interaction between Stressed in Base and Vowel Height. Vowels that are stressed in the base have higher ratios than those that are unstressed in the base (β = .11, p < .01). The significant interaction with vowel height indicates that the effect of being stressed in the base is stronger for mid vowels (β = .09, p < .05). While there is a main effect of being stressed in the base, mid vowels drive the effect and low/high vowels show much weaker effects. Duration may reflect actual surface stress for all vowels. However, since the effect is driven by mid vowels, it could also be a byproduct of the allophonic differences between [e, o] and [ɛ, ɔ].

There are also significant main effects of Vowel Position (from the beginning of the word) and Distance from Primary Stress (moving backwards from primary stress). Because these are effects on ratios, however, they are not very informative. Counting from the beginning of the word, the second, third and fourth vowels ([pozit∫iva-mẽt∫i]) all have smaller ratios than the vowel in the initial syllable ([pozit∫iva-mẽt∫i]) (2nd position: β = –.05, p < .05; 3rd position: β = –.09, p < .01; 4th position: β = –.16, p < .01). These vowels are not necessarily shorter than the first vowel; they are more similar in special and normal suffix words than initial vowels are. In terms of clash, recall that vowels in clash position are stressed in the base and adjacent to primary stress in the derived word ([kaˈfɛ], [kaˌfɛˈzĩɲu]). Moving backwards from primary stress, vowels in clash position have higher ratios than those one vowel away (β = –.15, p < .001), two vowels away (β = –.18, p < .001), three vowels away (β = –.22, p < .001), and four vowels away (β = –.26, p < .001). The negative estimates indicate that ratios are lower for vowels further away from primary stress than for vowels in clash position. Vowels adjacent to primary stress that are not stressed in the base do not cause clash ([paˈsifika], [paˌsifikamẽt∫i]). Their ratios do not differ significantly from those that create clash (β = –.13, p = .10). Clash could cause retraction in cases like [kafɛˈzĩɲu] → [kafɛˈzĩɲu], such that /a/ lengthens and /ɛ/ shortens. This would increase the ratio of /a/ and decrease the ratio of /ɛ/, since the retraction does not occur in the normal word comparison. In short, vowels do not shorten to alleviate clash in special suffix words. The data provide no evidence for retraction, but the stimuli were not designed for this purpose and the results should be taken as merely suggestive.

The raw duration model (on stressed base vowels only) shows similar results (model not reported). There is a main effect of Suffix Type: base stressed vowels are longer in special suffix words than in normal suffix words (β = .01, p < .001). A significant interaction between Suffix Type and Vowel indicates that the effect is strongest for mid vowels (/ɛ/: β = .04, p < .001; /ɔ/: β = .02, p < .001), and significantly weaker for /i u/ (/i/: β = –.009, p < .001 ; /u/: β = –.008, p < .05). Vowels are also shorter in longer words (β = –.007, p < .001), which is expected because of compression. While the duration ratio model predicts larger ratios in longer words, this effect is small. Furthermore, larger ratios in longer words does not mean vowels are longer in longer words. Instead, in a given word pair (positivamente, positividade), the difference between a vowel in a special and normal suffix word is greater than that same difference in a shorter word set (cafezinho, cafeteira). It is not surprising that compression effects are absent, since the ratios control for word length by comparing vowels in words of (mostly) equal length. Finally, vowels in clash position are longer than those not adjacent to primary stress. In comparison to stressed base vowels immediately adjacent to primary stress, vowels one and two positions away from primary stress are shorter (β = –.01, p < .001, and β = –.04, p < .001, respectively). This replicates previous findings that vowels immediately adjacent to primary stress are longer than those earlier in the word (Gama Rossi 1998; Arantes & Barbosa 2002). These results are the same as the ratio model: clash is not resolved by shortening. Crucially, the effect of base stress holds despite the potential for clash resolution, which would, if anything, undermine the results.

The duration differences between base stressed mid vowels in special suffix words and their counterparts in normal suffix words are likely perceptible, but it is not clear that the differences for other vowels are. Figure 2 plots the duration of stressed base vowels in special and normal suffix words: all vowels are longer in special than in normal suffix words, but the effect is small for all but the mid vowels. The JND (just noticeable difference) for English vowel duration is around 20–25ms (Huggins 1972; Klatt & Cooper 1975; Klatt 1976). In the current study, the difference in duration between vowels in special and normal suffix words is over the JND only for /ɛ, ɔ/ (35–36ms longer in special suffix words than in normal suffix words) (Table 2). The raw measurement data modeled lacks /e, o/, since no target words have underlying stressed /e, o/. For base stressed /a, i, u/, the duration differences between normal and special suffix words fall well below the threshold.

Table 5 also highlights differences in inherent vowel duration and the potential confounds of comparing vowels of different qualities. Regardless of whether /i/ is stressed or unstressed, it is always shorter than stressed or unstressed /a/. These inherent differences make comparisons like those in studies discussed in Section 4.2 problematic.

In sum, duration suggests stress maintenance on the base: vowels that are stressed in the independent base are longer in special suffix words than in normal suffix words, reflecting stress maintenance in the former. The effect is strongest for mid vowels, which reduce the most when unstressed (Section 2.1). The effects for /a, i, u/ are smaller in magnitude and potentially imperceptible. If the duration effect holds robustly only for mid vowels, this could indicate stress at a point in the derivation when mid vowel reduction takes place, rather than surface stress.

Figure 3 shows special:normal intensity ratios for vowels that are stressed and unstressed in the base, which hover around 1 for all vowels.

The final model (Table 6), however, has a marginally significant effect of Stressed in Base in the expected direction. Vowels that are stressed in the base have significantly higher intensity ratios than those that are unstressed in the base (β = .003, p =.05). For example, in the base [eduˈkada], the penultimate vowel is stressed. This vowel is louder in the special suffix word [edukaˈdʒĩɲa] than in the normal suffix word [edukaˈt∫iva]. In contrast, the unstressed /u/ in the base [eduˈkada] is approximately the same intensity in the special suffix word [edukaˈdʒĩɲa] and in the normal suffix word [edukaˈt∫iva]. Intensity is not a robust correlate of stress in Brazilian Portuguese, but increased intensity would, if anything, reflect stress maintenance. The model of raw intensity shows the same results: stressed base vowels in special suffix words are louder than those in normal suffix words (β = .82, p < .001), and this effect is weakest for the high vowels.

The effects are significant, but small and potentially imperceptible. Flanagan (1955) reports the minimum JND for intensity at 1.2dB. In my study, the differences between stressed base vowels that maintain stress and those that lose it fall well below the JND (Table 7). However, regardless of perceptibility, the realization is consistent and correlated with base stress. Intensity potentially provides phonetic evidence of stress maintenance on all vowels, and the effect size does not differ significantly by vowel quality.

Recall that large F1 differences indicate that two instances of the same vowel differ in height ([kafɛˈzĩɲu]: [kafeˈtejɾa]); small differences indicate that the vowels are close to the same height ([pozit∫ivaˈmẽt∫i]: [pozit∫iviˈdadʒi]). The measure is the absolute difference in magnitude between two measurements of F1. All speakers who reduced did so by raising (see Appendix B, Supplementary File 1, for individual results).

Figure 4 plots F1 difference measures by vowel height. Mid vowels that are stressed in the base (/ɛ, ɔ/) have high difference measures, reflecting large differences between height in special and normal suffix words. Unstressed base mid vowels /e, o/ (all upper-mid, since unstressed base vowels cannot be lower-mid), have smaller difference measures, indicating similar height in both word types. For high and low vowels, however, the difference in height between special and normal suffix words does not depend on if the vowel is stressed in the independent base or not. To illustrate, the difference in height between stressed base /i/ in the special word [pozit∫ivaˈmẽt∫i] and in the normal suffix word [pozit∫iviˈdadʒi] is equal to the difference between unstressed base /i/ in [pozit∫ivaˈmẽt∫i] and in [pozit∫iviˈdadʒi].

The final model for F1 differences (Table 8) has a significant main effect of Vowel Height and a significant interaction between Vowel Height and Stressed in Base. I limit the discussion to these relevant predictors. There is a main effect of vowel height, whereby low vowels have overall higher ratios than high vowels (β = .55, p < .001). There is no main effect of being stressed in the base. However, the interaction between Vowel Height and Stressed in Base indicates that being stressed in the base has an effect for mid vowels (β = .69, p < .001). A stressed base mid vowel is very different in a special suffix word (it is lower) and in a normal suffix word (it is higher), but an unstressed base mid vowel is approximately the same height in both word types. Low and high vowels are approximately the same height in normal and special suffix words, regardless of base stress. Mid vowels show stress maintenance in special suffix words by maintaining vowel height, while high and low vowels do not.

The raw F1 models (F1 normalized by speaker) were built separately for each vowel. Recall that they include only the subset of vowels that are stressed in the base (/a, ɛ, i, ɔ, u/), thus excluding upper-mid vowels. These models confirm that lower-mid vowels stay lower-mid in special suffix words and raise in normal suffix words (β = .38, p < .05). There is no effect of suffix type for other vowels (/a/: β = –.21, p = .07; /i/: β = .002, p = .98; /u/: β = .03, p = .80). If there were to be another effect, we would expect it in /a/, which has been reported to raise slightly when unstressed (Barbosa & Albana 2004).