The traditional method of assessing students' writing puts too much emphasis on the grammatical errors, which often frustrates and bores student writers. In view of this situation, this paper, employing systemic functional approach, puts forward a new perspective on assessing writing — a textual metafunction perspective, by analyzing the Thematic structure both above and at the clausal level and uncovering the strengths and weaknesses of the student's writing, and giving it a full functional analysis from the three metafuncitons. In the end, the paper points out the pedagogical implications of this method in English writing assessing and teaching.
