Transfer at the level of argument structure or morphology: a comparative study of English and Persian unaccusative and unergative verbs

Transitivity alternation refers to the causative/inchoative alternation of some unaccusative verbs. Different languages use different patterns to show transitivity alternation morphologically. While some languages like English use zero or no overt lexical marking, other languages (e.g. Spanish, Turkish, and Japanese) use overt morphological markers to show transitivity. This study aims to investigate the degree to which similarities and/or mismatches between English and Persian influence the use of unaccusative and unergative verbs by Persianspeaking learners of English. Based on different verb types in English and Persian, seven verb categories were identified as the basis for comparison. A forced-choice elicitation test including 48 items was developed based on these seven verb categories. A proficiency test was also used to divide participants (116 undergraduate students of English) into high and low proficiency groups. The results revealed findings more in line with transfer at the morphological rather than the argument structure level (Montrul, 2000). Alternating unaccusatives with similar equivalent structures for transitive/intransitive pairs in Persian and non-alternating unaccusatives with different structures for transitive/intransitive pairs in Persian seem to be the most difficult verb categories for learners. The effect of proficiency level was also significant on the recognition of correct structures.