Do Heavy-NP Shift Phenomenon and Constituent Ordering in English Cause Sentence Processing Difficulty for EFL Learners?

Heavy-NP shift occurs when speakers prefer placing lengthy or “heavy” noun phrase direct objects in the clause-final position within a sentence rather than in the post-verbal position. Two experiments were conducted in this study, and their results suggested that having a long noun phrase affected the ordering of constituents (the noun phrase and prepositional phrase) by advanced Iranian EFL learners. In the first experiment, we found that when the direct object NP is lengthened by adding extra linguistic information, participants tended to form sentences with heavy-NP shift structures more often than the basic word order (subject direct object prepositional phrase). The results of the grammaticality judgment task used in the second experiment indicated that participants regarded sentences with the shifted word order as being grammatical more often than being awkward and ungrammatical. These findings support the idea that advanced EFL learners, quite like native speakers of English, show a strong tendency towards forming shifted structures when the length of the direct object NP increases. The results obtained from this study can be attended to in developing materials for learners in different levels of proficiency. Furthermore, teachers can use the results to adapt their teaching of the structure to learner's level of proficiency by considering the processing difficulty the structure might cause.