[[alternative]]Using Systemic Functional Linguistics perspective to explore the reading comprehension of different scientific text structures--Take “Heat and Temperature” for example

[[abstract]]The purpose of this study is to explore the scientific text structures and its effects on reading comprehension. Current edition of physical science textbook is employed as an analysis blueprint. This study consists two parts. First, using the SFL theory to analyze the scientific text structure in junior high school. Second, to compare the effects of reading comprehension between different texts. Two texts were developed as the reading materials in the present study. The “traditional” text was edited according to the text of the “Heat and Temperature” in physical science textbook, and the “SFL” text of the same topic was re-written according to the principles of SFL, such as “genre theory”, “conjunctive relations” and “nominalization”. These two texts consist 1600, 1400 words, respectively. Two experiments were designed to explore the relations of the four dimensions of reading comprehension and pupil’s prior knowledge. Twenty-eight and sixty-night 8th -grade students participated in these two experiments. The main findings of this study are as follows︰(1) Students who read the “SFL” text spent more time in reading-text and doing-posttest than those who read the “traditional” text. (2) SFL text was more helpful for middle prior knowledge students in applying text-related comprehension.(4) SFL text was more helpful for low prior knowledge students in the vocabulary, literal understanding and making inference. Drawing upon the findings, the implications of science text writing were discussed, and directions for future study were proposed.