This article deals with the identification and internalization of complex structures in oral communication by students of English as a foreign language. Limited lexical skills or phonological misperception are often considered as major obstacles to the non-native competence in oral reception. This article hypothesizes that the lack of mastery of some typical grammatical and syntactic structures in use in conversational English disrupt the flow of communication between natives and non-natives and limit the oral competence of foreign language learners. The study explored inter-comprehension, adjustment and re-adjustment phenomena in the DIDEROT-LONGDALE longitudinal corpus of conversations between natives and Bachelor’s students from Paris-Diderot University (now University of Paris). The initial hypothesis was that the reception difficulties displayed by the students were not only caused by lexical ignorance, oral misperception or lack of sustained attention. They also resulted from the subjects’ failure to grasp complex oral forms produced by the native assistants: non-canonical or rare interrogative structures, anaphoric forms and ellipses as well as long utterances with multiple clauses. After analyzing examples of interactional dysfunction, the article discusses the inter-adjustment strategies used by the interlocutors to resume the conversation. It also questions their long-term efficiency for scaffolding linguistic competence. The analysis of eight recent textbooks used in secondary schools shows that students are seldom explicitly exposed to complex or non-salient conversational features. Consciousness-raising strategies are then suggested in the last part: Focus-on-Form techniques such as the scanning of electronic conversational corpora by concordancing tools to extract interrogatives, the identification of co-reference chains (Stanford CORE NLP Suite) or the qualitative targeting of anaphoric elements.