This study was conducted to investigate the use of modals in narrative writing of English for foreign advanced adult learners. This study had two objectives: first, to determine the distribution pattern of modals and, second, to see if the participants used the modals accurately in their compositions. This was a learner corpus study, based on students' writings. The participants in this research were 136 randomly selected adult advanced learners attending English learning programs in six English institutions in Shiraz, Iran. The data used in this study were obtained from the written data consisting of compositions, which volunteers need to write. The study applied the qualitative method, which was supplemented with some descriptive statistics from a concordance. The WordSmith Tools, Version 4.0, was used for the purpose of this research. It was found that there were some discrepancies in the frequency of modals used by native speakers and the ones used by our EFL advanced students. In addition, students were rather competent in producing modals syntactically but simplification features were also detected in these learners' compositions as a means to overcome their limitations in using modals in English.