de-是個用法較為復(fù)雜的前綴。它原是個拉丁介副詞，只出現(xiàn)在拉丁或法語借詞中。de-依附在詞根前，表示 down (from) 或away (from)的意思，有時則表示對詞根的強調(diào)，有completely 的意思。 后來，de-被英語所同化，變成一個相當(dāng)活躍的派生前綴。它可以加在動詞或名詞之前，生成帶否定意義的動詞。當(dāng)它與動詞結(jié)合時，基本意思是to undo,表示“做（與原動詞）相反的動作”。當(dāng)它與名詞結(jié)合時，基本意思是to make down or away,表示“降低，剝離，取走”等動作。下面，我們按照de-的構(gòu)詞功能，分別予以介紹。

先觀察由de-與詞根結(jié)合的幾個具有代表性的例子。

decline [ de- = down 下；clin = to bend 彎；-e=>“to bend down彎下去”→]v. ① bend or slope downwards 下傾 / The road declines at the turn.到拐彎處路轉(zhuǎn)下坡了。② turn down; refuse 拒絕 / I have to decline your invitation because Mother is ill.媽媽病了，我只好謝絕你的邀請。

declination n. 傾斜；拒絕，謝絕

decrease [ de- = down 下;creas = to grow 變得；-e=>“ to grow downward 變得下降了”→] v. grow or become less 減少；減小/ Hunger decreases as one eats.吃東西時饑餓感就減少了。

debar [de- = away 外；bar = to shut 關(guān)=>“to shut away 把…關(guān)在外面”→]vt. shut out; prevent 排除；阻止 / He was debarred from club membership because of the scandal. 因為那件丑聞，他被俱樂部拒之門外。

detract [ de- = away 離；tract = to draw 抽=>“to draw away 抽離”→]v. take away a part; remove some value 減損；貶低 / The ugly frame detracts from the beauty of the picture. 難看的畫框影響了這幅畫的美麗。

detraction n. 減損；貶低