This study examines the role of receptive vocabulary knowledge on outcomes of the TOEFL reading comprehension task. Participants included 18 native speakers of Spanish learning English as a foreign language and 17 native speakers of English ranging in age from 19-25 years. Lexical stimuli were presented auditorily and were divided into "easy" and "hard" words based on both frequency and lexical neighborhood density. To increase difficulty, stimuli were distorted to simulate what is heard through a cochlear implant (CI). Linear regression showed that, for bilingual participants, higher scores on the TOEFL reading comprehension task were predicted by higher rates of accuracy for "easy" words. The theory of complementary distribution within the bilingual lexicon indicates that if a bilingual individual has a higher proportion of English-language words in their lexicon that are more colloquial (easy), they are less likely to have proficient knowledge of higher-level vocabulary necessary for university-level reading comprehension. This indicates that educators of English as a foreign language learners must work to improve knowledge and proficiency of more difficult vocabulary tokens. [For the complete proceedings, see ED672804.]