本文以系統功能語言學（SFL)觀點，探討學生對不同科學文本的閱讀理解。文本有二：依SFL之技術性建構及語體組織設計的SFL文本（ST)及以國中科 學文本為主的傳統文本（CT)，分別供實驗組及對照組閱讀，並以先備知識測驗（PKT)及閱讀理解測驗（RCT)瞭解學生的先備知識及閱讀理解。研究分為二個實驗，實驗一分析二組學生的閱讀及作答RCT時間，實驗二則探討學生對文本的閱讀理解。
結果顯示實驗組的閱讀及作答時間明顯多於對照組，意味著ST使學生花費較多時間仔細閱讀及作答。整體而言，實驗組閱讀理解的表現較佳。此外，實驗組之低先備知識者在句義、推理及應用的表現明顯較佳，顯示ST結構似乎可促進學生的閱讀理解，對低先備知識者尤具助益。

The purpose of this study was to explore the effects of different science texts on students’ reading comprehension, as analyzed from the perspective of Systemic Functional Linguistics (SFL). Two texts were designed that the SFL text (ST) was designed by the theory of technicality construction and genre organization in SFL for the ST group, and the Conventional Text (CT) was the standard secondary school text for the CT group. Prior Knowledge Test (PKT) and the Reading Comprehension Test (RCT), the instruments, were designed to probe the students’ prior knowledge and reading comprehension. There were two experiments. The first analyzed the speed of reading and answering RCT for both groups, while the second compared the reading comprehension level in the two groups.
According to the results, students in the ST group spent a significantly longer reading and answering time on the RCT, which implied that much more effort was needed by them to read and answer this test carefully. Additionally, the reading comprehension in the ST group was better than that in the CT group. Furthermore, the performance of the low prior knowledge students in the ST group was significantly better than that in the CT group in terms of the literacy, inference, and application. These results implied that the ST could facilitate the students’ reading comprehension, especially for those low prior knowledge students.