本研究目的為探討一位經驗豐富的國小自然雙語教師，如何以教學語言與多模態教學來幫助學生建構科學知識。研究方法採用課室觀察與深入訪談個案進行資料的收集，透過教學語言及多模態教學的編碼分析與整理以回應研究問題。研究分析結果發現個案以教學語言與多模態教學作為教學鷹架時，會同時考量學生的認知需求、教學目標及評量方式、自然雙語課程的特殊性及不同呈現形式的特性。此外，研究結果也可發現個案會適時的調整教學語言及多模態教學鷹架來回應學生的學習狀況，並且顯示以教學語言與多模態教學作為教學鷹架可以作為未來教師或其他研究者進行自然雙語教學時的研究參考。

The purpose of this research is to explore how an experienced bilingual science teacher in elementary school helps students construct scientific knowledge with teaching discourse and multimodality teaching. The research method uses classroom observation and interviews with case teacher to collect data, and responds to research questions through the coding analysis and arrangement of teaching discourse and multimodality teaching. The results of the research found that when the case teacher used the teaching discourse and multimodality teaching as a teaching scaffold, she would simultaneously consider the cognitive needs of students, teaching goal and assessment, the particularity of science bilingual courses, and the characteristics of different modalities. In addition, the research results can also find that the case teacher will adjust the teaching discourse and multimodality teaching scaffold to respond to the learning situation of her students. The results of this study show that teaching discourse and multimodality teaching as a teaching scaffold can be used as a research reference for teachers or other researchers in science bilingual teaching.