This article is a corpus-based study of colloquial features, especially quasi-modals in English leerswritings. Via us?ing Longman Leers Corpus, British English 2006 and American English 2006, quasi-modals used in English language le?erswritings are compared with the real uses of quasi-modals in native speakerswritings. The results show that English language leers may have a problem with misusing colloquial-feature phrases, quasi-modals, in written registers.