本研究由114位台灣非英語系大學一年級生參與，其學生來自四個「大一英文」班級，所有學生皆為本地生，並在台灣學制下學習英文至少達九年，旨在探討兩種教學法對學生單字立即性及延遲性學習的影響。研究中的兩個教學法各為「純粹閱讀」及「閱讀＋單字焦點練習」；研究教材為四篇英文文章，每篇各有十個學生不熟悉的單字，四篇文章分別在四次的課程逐一教導，教學法則為上述兩種交替進行。研究工具以中譯版的「單字知識等級表」探討學生字彙習得及保存成效。研究結果顯示，四篇文章都證實「閱讀＋單字焦點練習」明顯有助學生立即記憶較多單字定義，然而，經過兩週沒有任何單字強化的情況下，只剩其中一篇文章顯示:接受「閱讀＋單字焦點練習」教學法的學生回憶明顯較多的單字。另外，比較兩種教學法對性別的差異發現，女生在兩種教學法的立即性單字習得都明顯比男生多，女生尤其受益於「閱讀＋單字焦點練習」教學法，統計結果指出，女生在兩週後仍比男生保留顯著的單字量。探討兩種教學對不同程度學生的影響顯示，程度最高和最低的兩班學生兩週後從兩種教學法中保留的單字量差異不大，然而，「閱讀＋單字焦點練習」教學特別有益於中等程度的兩班學生，此教學對字彙習得及保留皆有明顯助益。整體而言，本研究發現「閱讀＋單字焦點練習」在不同變項皆較有助單字習得，因此，本研究結論為台灣大學生能較有效的透過「閱讀＋單字焦點練習」教學法習得字彙。 The purpose of this study was to examine the effectiveness of two treatments, reading only (RO) and reading plus vocabulary enhancement activity (RV), on EFL college freshmen’s vocabulary acquisition and retention. A total of 114 subjects from four intact Freshman English classes of a private university in northern Taiwan participated in this study. All the participants were local Taiwanese students who have been learning English in the Taiwanese school setting for at least nine years. Students in the RO treatment were given a reading plus a supplemental reading while those in the RV treatment had to read and complete vocabulary enhancement activities. The two treatments were alternatively administered to each class during the study. Four readings were instructed in four one-hour sessions by the two treatments. Each class received each treatment twice during the study. Ten words which the participants had almost no knowledge of were targeted in each reading, so forty words in total were included. Two posttests were delivered to test word acquisition in each reading. One was the vocabulary acquisition test administered immediately after the intervention and the other was the delayed posttest administered two weeks after the instruction. The subjects were measured on both the immediate and delayed posttests by a modified Chinese version of Vocabulary Knowledge Scale (VKS). The result of the immediate posttests showed learners had highly significant word gains from the RV in all four readings. Yet without reviewing the words within the two-week interval the attainment waned. Only one reading showed the RV led to significantly better retention in the delayed posttests. When word acquisition of genders was compared, the female subjects outperformed significantly in the immediate posttests of both treatments. Consistently, the females assigned to the RV treatment retained significantly more words than the males in the delayed posttests. However, no significant difference between genders was found in the delayed RO treatment. When the effectiveness of the treatments was examined on classes of different proficiency levels, the result was that the scores in the RO and RV did not differ significantly in the highest and the lowest level classes. In contrast, the two classes which were in the middle level of the participating classes showed the RV led to significantly more word gains in both the immediate and delayed posttests. Due to the findings, the current study concluded that the RV was more effective in increasing word development of EFL learners.