本論文之研究目的乃在於研究字彙量多寡是否會影響大學生英語寫作能力。研究方法採質化與量化研究，計有 127位應用外語系與非應用外語系學生納入本研究調查對象，學生們均參與填答一份問卷調查，經調查研究結果顯示，在英語寫作課程或英語寫作考試之前，英語為外國語言之學生會自動自發練習與使用詞類變化及字彙，此乃足以驗證字彙量多寡確實會影響應用外語系英文組學生之寫作能力甚大。

The purpose of this study aims to investigate the effects of vocabulary knowledge on English writing at university level. Both quantitative and qualitative approaches were used in this study. 127 students were from an Applied Foreign Language Department and a non-English major department. Data was collected through questionnaires filled out by the students. To summarize, the results showed that EFL (English as a Foreign Language) students should acquire vocabulary voluntarily and practice the application of varied parts of speech often before having English writing courses or tests.