透過網路輔助的學術英文詞彙教學，我們探討此教學對二十五位台灣大學生的單字與寫作能力之影響。教學內容包含：直接的教學與字彙索引、線上小考、寫作與單字練習。評量工具為：單字廣度與深度測驗、寫作測驗，各在教學前後實施一次。四週後，進行第三次寫作測驗和問卷調查。結果指出學生的單字深度增加，廣度則無。根據單字頻率及寫作測驗的分析，教學後，學生於寫作中能正確地使用較多學術詞彙，其寫作能力也有進步。學生對教學成效也大致給予正面評價。因此我們認為利用網路輔助單字教學以擴展學生的單字使用能力是可行的。

Using web-enhanced lexical instruction based on the Academic Word List in an EFL course, we explored the effects of an eight-week vocabulary intervention (Coxhead, 2000) on the development of twenty-five EFL learners’ lexical and writing abilities. Three instructional features were included: (a) explicit academic vocabulary lessons (wordlists, weekly lecture notes and reading) plus concordancing practice, (b) online quizzes, and (c) pair writing and individual lexical logs. Measurement included a vocabulary size test and depth test plus a timed writing task administered before and after the instruction; four weeks after the instruction, the writing task and a questionnaire were given. The results indicate that the learners increased their lexical depth but not the size after the instruction. In the Lexical Frequency Profile analyses of the writing tasks, the learners used more academic words accurately in post-instructional writing compared with their entry level. Positive correlations were found between the learners’ post-instructional lexical and writing performances. We believe that web-enhanced lexical instruction is promising in expanding learners’ academic productive vocabulary. With advancement in academic vocabulary in writing, EFL learners’ academic literacy can be promoted so that they can fully participate in the academic community later.