本實驗之受測者分為三組，分別以線上字典、傳統的書面字典以及不提供任何字典的情況下閱讀兩篇難易度不同的文章。本實驗的研究主題之一在於探討查閱字典對閱讀理解是否有助益；當文章難度增加時，是否會影響受試者閱讀理解能力之表現。研究主題之二在於瞭解閱讀時查閱字典對於字彙習得有多少助益；當文章難度增加時，是否會影響受試者字彙習得之表現。研究主題之三是單字的查閱次數；當文章難度增加時，是否會影響受試者單字查閱率。研究主題之四在探討閱讀理解、字彙習得及單字查閱次數之間的關聯性。研究主題之五在了解是否電腦螢幕上查字、閱讀有助於受試者的學習興趣及學習成果。
本研究主要發現如下：
1. 在閱讀測驗的成績方面，三組受試者並無顯著不同，這表示查閱字典對閱讀理解並無明顯助益。三組受試者在難度較高的這篇文章上分數較為接近且得分較低。
2. 本研究發現閱讀文章的確有助於字彙習得，而且使用字典組表現明顯優於未使用字典組，且從兩週後的單字後測成績發現，受試者單字的遺忘率不到一個字，顯示閱讀文章不但有助於字彙習得且證實這類的字彙習得並非只屬於短期記憶而已。當文章難度增加時，受試者字彙習得的表現隨之變弱。
3. 使用線上字典的受試者，查閱的單字數遠超過使用傳統書面字典 (約有三倍)。當受試者閱讀較難文章時，查閱單字次數亦增加。
4. 單字查閱次數高者，字彙測驗分數亦高；字彙測驗分數高者，閱讀測驗分數亦高；然而單字查閱次數與閱讀理解卻沒有發現有顯著相關，也就是單字查閱次數高者，閱讀測驗分數卻不見得高。
5. 使用線上字典的受試者普遍認同在電腦螢幕上查字閱讀的快速、方便，但卻有專注力降低的隱憂。
本論文根據研究結果，提供了相關的教學建議。
1. 查字典可幫助提升學生的單字記憶力，所以學生應有查字典的習慣而不是只靠老師釋義。
2. 老師應教導學生如何有效地查閱字典，避免濫用字典。
3. 學生應該從閱讀中習得字彙，而不是從單字表中一個字、一個字單獨死背。
4. 訓練學生閱讀能力應靠學生自己理解文章，而不是老師逐字解釋、逐句翻譯來了解文意。
5. 學生除了增加單字量外，完整的文法、句型概念，亦是影響閱讀理解的關鍵， 此外教師應訓練學生熟悉閱讀技巧及策略。
6. 使用電腦教學時，老師必須要使用有效的方法讓學生專注在指定的課程上，以期讓電腦教學的功能得以發揮。

Three reader groups read two texts of different difficulty levels respectively with online dictionary, with conventional paper-printed dictionary, and without dictionary. The first topic is about the effect of dictionary check and the effect of text difficulty on the subjects’ text comprehension. The second topic is about whether dictionary check will enhance vocabulary learning while reading and whether text difficulty will influence it. The third topic is the lookup behavior. The fourth topic is the correlation among comprehension, vocabulary learning and lookup behavior. The fifth topic is the participants’ perceptions of using online learning system.
The following are the major findings of the study.
1. There was no significant difference between groups on comprehension tests. When reading the more difficult text, the scores of comprehension tests became lower.
2. Dictionary check significantly enhanced vocabulary learning. Besides, less than one word loss indicated that it was not merely short term retention. When the difficulty level of the text was raised, the subjects’ performance became less satisfactory.
3. The frequency of words looked up in the online dictionary group was about three times higher than that in the paper-printed dictionary group.
4. There was significant positive correlation between the lookup behavior and vocabulary retention and between the vocabulary retention and text comprehension. No correlation between the frequency of lookup and comprehension tests was found.
5. The subjects agreed on the speed and convenience of online learning system but they confessed that their concentration level became lower.
Some pedagogical implications were offered as followed,
1. Students should be encouraged to look up words to help them enhance retention.
2. Students should be guided to consult the dictionary wisely and effectively.
3. Teachers should have the students learn and retain vocabulary through reading instead of giving them a long list of new words to memorize.
4. Teachers should have students comprehend the text by themselves instead of translating it into Chinese line by line and stopping at every unknown word.
5. Teachers should make students familiar with the effective reading skills and strategies and develop a complete concept of sentence patterns and structures.
6. When applying computer assistance language learning to the classroom, teachers should come up with some ideas to make students more attentive on the given task.

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