ABSTRACT
According to the Unaccusative Hypothesis (Burzio, 1986), there are two types of intransitive verbs, unaccusative and unergative, each associated with a different underlying syntactic configuration. An unaccusative verb takes a theme argument base-generated in object position while an unergative verb takes an agent argument base-generated in subject position. This chapter explores how the unaccusative/unergative distinction is represented in the minds of language learners. Following Levin and Rappaport Hovav (1995), it is assumed that unaccusativity is syntactically represented but semantically determined. Languages exhibit semantic and syntactic reflexives of the contrast, and various diagnostics have been identified. Empirical research using such unaccusative diagnostics in languages including English, Italian, Spanish, and Japanese provide evidence that language learners possess knowledge of the two types of intransitive verbs. More recent studies with psycholinguistic methods on sentence processing also support the view that learners are sensitive to the syntactic distinction of unaccusative and unergative verbs. At the same time, unaccusative verbs, but not unergatives, cause problems to learners, as reflected in overpassivization errors typically observed among learners of English from intermediate to even advanced-proficiency levels.
