Language Teaching Research Quarterly

The issue of non-native speakers’ divergence from L2 input has gained popularity in the field of second language acquisition during the previous decades. Many significant scholars have joined the discussion and tried to explain this phenomenon through various models and frameworks. In this regard, the present study discussed domains of divergence within the framework of interpretability hypothesis. To this end, syntactic structures of future perfect progressive tense were compared in English and Persian. To examine the validity of Interpretability Hypothesis (IH), 30 Iranian L2 learners at intermediate and advanced levels were selected based on the oxford quick placement test. Further, learners were required to answer two translation tests containing English to Persian (comprehension test) and Persian to English (production test) sentences. Results revealed that learners had no problem in comprehension of this tense; however, when it came to production, they experienced some instances of divergence. Based on the findings, underpinnings of IH are supported in the sense that the logically interpretable English future perfect progressive tense poses little problem for learners whose L1 lacks the tense phonologically. Moreover, the results showed that Persian learners resort to some other compensatory tenses to express futurity in their L1.