有許多的實證研究都證明第一語言的翻譯在第二語言學習有其價值。
Hulstijn,Hollander and Greidanus (1996)比較閱讀文章旁邊用學生的一語和二語的注釋(marginal gloss)，結果發現以學生的一語比較容易幫助學習，Laufer and Shmueli (1997)也呼應這樣的結果；Lotto and De Groot (1998) 則比較以第一語言和圖片作為示意的情況，結果發現以學生的一語比圖片的呈現，學生對於新詞記得更久(retention)；Grace (1998)則發現英語母語者學法語的時候，學習者認為在能夠有一語的情況下，比較容易確認正確的意思；Prince (1996)發現，透過一語翻譯的情況對於程度較差的學習者而言，比較容易能夠去回想(recall)起新詞。
這並不是說學習二語一定要依靠第一語言翻譯，第一語言之所以有價值，在於其能夠讓學習者將新知識和舊知識連結在一起，去激發已經穩固的詞彙網絡。學習新詞的時候，之所以要激發先前的知識的因為它以經是個連結綿密的資訊網，一但新的詞彙能夠整合到這個資訊網裡頭，只要有一點點連結，學習者就容易喚回詞彙。許多研究都支持這樣子的說法(Stahl, 1983; Stoller & Grabe, 1993; Martin,Martin & Ying, 2002; Schmitt and Schmitt (1995) 。
References
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