大塚 祐子

This study explored sentence processing in two typologically distinct languages: Korean, a verb-final language, and Tongan, a verb-initial language. The first experiment revealed that in Korean, sentences arranged in the scrambled OSV (Object, Subject, Verb) order were processed more slowly than those in the canonical SOV order, highlighting a scrambling effect. It also found that sentences with subject topicalization in the SOV order were processed as swiftly as those in the canonical form, whereas sentences with object topicalization in the OSV order were processed with speeds and accuracy comparable to scrambled sentences. However, since topicalization and scrambling in Korean use the same OSV order, independently distinguishing the effects of topicalization is challenging. In contrast, Tongan allows for a clear separation of word orders for topicalization and scrambling, facilitating an independent evaluation of topicalization effects. The second experiment, employing a maze task, confirmed that Tongan’s canonical VSO order was processed more efficiently than the VOS scrambled order, thereby verifying a scrambling effect. The third experiment investigated the effects of both scrambling and topicalization in Tongan, finding that the canonical VSO order was processed most efficiently in terms of speed and accuracy, unlike the VOS scrambled and SVO topicalized orders. Notably, the OVS object-topicalized order was processed as efficiently as the VSO canonical order, while the SVO subject-topicalized order was slower than VSO but faster than VOS. By independently assessing the effects of topicalization apart from scrambling, this study demonstrates that both subject and object topicalization in Tongan facilitate sentence processing, contradicting the predictions based on movement-based anticipation.

This paper examines the null arguments occurring in adverbial 'o-clauses in Tongan, whose characteristics are distinct from other kinds of empty categories attested in the language. I argue (a) that the empty category in question should be understood as a phonetically null SE anaphor and (b) that local-and medium-distance binding of SE anaphors must be licensed by Agree with the functional category that assigns the primary case (i.e., T in accusative languages and v in ergative languages). The study also observes that 'o-clauses are similar to telic to-clauses in English as well as control subjunctives in Balkan languages in that they contain anaphoric tense, and suggests that some instances of what has been regarded as PRO in the literature might be better understood as an instance of a null SE.

This paper proposes that syntactic ergativity should be understood as a construction-based phenomenon rather than a parametric property that defines a subset of morphologically ergative languages. It argues that syntactic ergativity arises when the relevant operation is sensitive to (abstract) Case. Since not all syntactic operations are sensitive to Case, it is expected that some morphologically ergative languages do not show syntactic ergativity, or even demonstrate syntactic split ergativity. As an illustration, two types of coordination reduction in Tongan (Polynesian) are examined: pea-coordination showing an ergative/absolutive pattern and mo-coordination showing a nominative/accusative pattern. It is argued that DP ellipsis in pea-coordination is a Case-sensitive operation, i.e., PF deletion based on featural identity, whereas mo-coordination involves a null pronoun and LF copying, which is based on positional identity, regardless of Case.

This paper examines the sociolinguistic situation in Tonga and discusses its relevance to language maintenance in Polynesia. The environment surrounding Tongan is not visibly ominous: it is an official language of an independent state and is spoken by a sizable population in a predominantly monolingual community. Tongan represents an instance of language shift as a result of globalization, wherein a speech community voluntarily gives up its indigenous language(s) for another, more socioeconomically beneficial language, in this case, English. The paper proposes that language endangerment should be understood in terms of a unit larger than the nation-state. This is particularly relevant in the Polynesian context, in which international borders are obscured by transnational migrants. The paper also discusses some positive roles the diasporic communities may potentially play in language maintenance.

While the Tongic subgroup of Polynesian, consisting of Niuean and Tongan, is defined by a number of shared innovations, Niuean is known to exhibit phonological and lexical features that can be taken as evidence of Eastern Polynesian (EPN) influence. Niuean also shows syntactic features that are prominent among EPN languages, but absent in Tongan. This paper examines whether these syntactic features can be taken to be shared innovations and hence constitute a basis for a subgroup including EPN and Niuean. The current study suggests that convergent development is the probable explanation for the syntactic similarities between Niuean and EPN.

The so-called definitive accent (DA) in Tongan has been analyzed in various ways in the literature: as stress shift from penultimate to final vowel, as simultaneous stress reduction on a penult and stress addition on an ultima, and as addition of a syllable by repetition of the final vowel. This study investigates each of these analyses empirically in order to establish the phonology of DA in Tongan. Our findings support Melenaite Taumoefolau's proposal that definite NPs are formed by repetition of the NP-final vowel, and thus a morphological analysis of DA as reduplicative suffixation. Moreover, our findings substantiate an account of Tongan in which stress is unexceptionally penultimate in a foot, and in which "long vowels" and "diphthongs" are to be considered sequences of two syllables, as suggested by Taumoefolau.