摘要：This study aims at investigating first language attrition in Persian speakers of English as L2. Three groups are compared: Persian monolinguals, early bilinguals and late bilinguals. An acceptability judgment test is used in which the test sentences consist of pairs of sentences each of which follow either the English structure or the Persian structure in three syntactic areas of relative clause, adverb position and pro-dropping which constitute three main areas of syntactic differences between Persian and English. The results revealed that the type and degree of L1 attrition that early bilingual speakers undergo is different compared to late bilinguals and the degree of L1 education conditions attrition. The implication is that age of L2 acquisition has a major influence on how bilinguals represent their L1: late bilinguals often retain a large amount of underlying competence in their first language while early bilinguals lose it more quickly.
