| Since grammatical metaphor theory is initially put forward by Halliday, the theory is mainly applied to the analysis of scientific discourse. Actually, GM is pervasive in all types of adult discourse, so the passages in CET-4 reading comprehension make no exception. EFL learners always find some difficulties beyond them in CET-4 reading comprehension, and grammatical metaphor might constitute one of the difficulties in their reading comprehension. Thus the author makes an empirical study to investigate the distribution of GM in CET-4 reading passages and its influence on reading comprehension, with an aim to address the following questions: whether grammatical metaphor is a common phenomenon in CET-4 reading passages, whether grammatical metaphor hinders students'reading comprehension and whether there is a relationship between the frequency of grammatical metaphor occurrences and the difficulty of reading comprehension.In order to answer the research questions, two parallel classes are chosen as the research subjects. They are required to do test paper A and B respectively and mark the time they use. The two test papers are identical in every way except that in test paper A, the four passages are the original version containing grammatical metaphors, while in test paper B, the grammatical metaphors in passages are turned into congruent forms. After collecting the test papers, the author respectively analyzes the test results achieved by the two groups of subjects from a quantitative approach and makes some discussions on the test results, including the distribution of GM in test paper A, the differences of the time spent and scores achieved in doing test paper A and B, and the relation between the frequency of GM occurrences and the difficulty of reading comprehension. The research results are listed below: 1) GM is a common phenomenon in CET-4 reading passages and the most frequently used type of GM in CET-4 reading passages is ideational GM; 2) the comprehension of the metaphorical forms takes more time and is more difficult than that of the congruent ones, that is, grammatical metaphor will hinder students'reading comprehension to some extent; 3) the frequency of GM occurrences and the difficulty of reading comprehension is positively correlated.Based on the finding that metaphorical expressions can give rise to more difficulties to EFL learners in reading comprehension, the author presents the factors of GM to increase the reading difficulties, including the dual/more semantic features of GM and the complexity of metaphorical realizations; and makes an exploration on the comprehension processes of GM, i.e. how to transfer the metaphorical realization into its congruent realization in our minds. The study has some theoretical and pedagogical implications. It contributes to the development of GM theory further. In addition, it gives us some enlightenments for the future English teaching and helps EFL learners improve their grammatical metaphor competence in the process of reading comprehension. |