本研究主要的目的有二：一是探討學生在英語學習時會產生的錯誤類型，並設計在溝通脈絡下的結構取向英語教學課程。二是探討在溝通脈絡下的結構取向教學對國中生英語學習表現的影響，依據研究目的，本研究者先以英語高、中、低能力各五位學生採質性研究法來瞭解其英語學習的錯誤類型。結果發現：這些學生在英語學習時會有跨語言和語言內部兩類錯誤型產生並據此來設計實驗教學課程。在實驗教學方面以70名英語低成就學生為對象，藉由英語後設認知策略量表與英語成就測驗（前、後測）等工具的實施，以二因子混合設計變異數分析的方法進行統計處理，並採質性方法來深入瞭解實驗組學生的英語學習變化情形。結果發現：本研究的實驗教學課程有助於維持實驗組學生在後設認知與英語學習成就上的表現，反觀控制組學生在這些方面則從初期到後期呈逐步下滑的趨勢。再者，實驗組學生會善用策略來對自己常犯的英語錯誤進行監控、評鑑與修正，所以他們對英語學習更有信心也更願意去學習。

The purposes of this study are : (1) to investigate students’ errors in learning English with the use of qualitative analyses and further to design a form-focused instruction program in communicative contexts; (2) to examine the effects of such program developed by the researcher.In order to accomplish these purposes, the researcher needs first to investigate students’ errors in learning English with the use of qualitative analysis involving thinking-aloud and thinking-by-questioning methods. Participants are 15 eighth-grade students divided into three groups of high, middle, and low levels in English. Based on the errors made by the students, the results can be classified into two patterns: interlingual and intralingual. According to the results of error analyses, the researcher has therefore designed a form-focused instruction program in communicative contexts and examined the effects of the program.There are totally 70 eight-grade students with low English performance in two groups, experimental group and control group. By utilizing Metacognition Strategies Inventory and English Achievement Tests (pre-test after-test) as primary instruments, the data acquired are then statistically studied by two-way mixed-design ANVOA, with a deeper focus on the English learning process in the experimental group by using a qualitative analysis. The results indicates that the form-focused instruction program in communicative contexts could help the students in the experimental group maintain their performances in metacognition strategies and English learning achievements (reading, writing, and speaking). However, the performances of the control group in these inventories and tests tend to decline. What is more, after class, the students in experimental group are able to apply the strategies to retain their learning interests and to actively monitor, evaluate, and modify their English learning habits. In short, form the analyses of students’ English learning process, students in the experimental group become more confident and will to learning English after the form-focused instruction program.