Taking advantage of vast electronic text resources, the corpus-based approach has contributed a lot to linguistic research. It can be applied to almost all areas of investigations in linguistics (Biber, Conrad and Reppen, 1998) . At the same time the role of corpora in the language classroom remains a great controversy. Some linguists believe that corpora are of great help to the language teachers whereas some others hold a negative view on its application to language teaching. As this argument is still under debate , many language teachers are applying corpora to their own teaching and this is the best way to evaluate the adoption of corpora in language classroom.
