DDT, the most powerful pesticide the world had ever known,exposed nature’s vulnerability. Unlike most pesticides, which effect- __1__ tiveness is limited to destroy one or two types of insects, DDT is __2__ capable of killing hundreds of different kinds at once. Developed in　1939, it first distinguished itself during the World War II, cleaning __3__ South Pacific islands of malaria-caused insects for U.S. troops, while __4__in Europe being used as an effective de-lousing power. Its inventor　was awarded by the Nobel Prize. __5__ When DDT became available for civilian use in 1945, there were　only a few people who expressed the second thought about this __6__ new miracle compound. One was nature writer Edwin Way Teale,who warned, “A spray as discriminate as DDT can upset the economy __7__ of nature of all insects are good, but if they are killed, things __8__ go out of kilter right away.” Another was Rachel Carson, who　wrote to the Reader’s Digest to propose an article about series of __9__ tests on DDT being conducted not far from which she lived in Maryland. __10__

　　參考答案：

　　1.which—whose。whose在這里作關(guān)系限定詞，與effectiveness構(gòu)成名次詞組在關(guān)系分句里作主語(yǔ)。whose的主語(yǔ)可以是人，也可以是物。

　　2.destroy—destroying。be limited to 詞組里的to并不是不定式標(biāo)記to，而是介詞to，要謹(jǐn)訪介詞to“冒充”不定式to。其他類似的詞組還有be opposed to, object to, get used to等等�？荚嚧�

　　3.cleaning—clearing。clean和clear這對(duì)形近而且意近的動(dòng)詞容易被混淆，但是clean指“使某地方?jīng)]有灰塵，使干凈”，而clear強(qiáng)調(diào)“清理不需要的東西，而且clear 可與of連用，而clean很少。(這兩個(gè)詞的改錯(cuò)之前也有遇到過(guò)，大家都要記住啦!)

　　4.caused—causing。此句中malaria-causing insects 相當(dāng)于insects that caused malaria，因此是主動(dòng)關(guān)系，所以應(yīng)選擇-ing形式。

　　5.by-/。the Nobel Prize實(shí)際上是award的另一個(gè)賓語(yǔ)，還原成主動(dòng)結(jié)構(gòu)是…awarded the inventor the Nobel Prize.所以這里應(yīng)刪掉by。

　　6.the-/。短語(yǔ)second thought或second thoughts意為“仔細(xì)斟酌，三思”，如：Robert didn’t give a second thought to borrowing $2,000 from him.

　　7.discriminate-indiscriminate。discriminate有“區(qū)別”之意，indiscriminate意為“不加以選擇，不分青紅皂白”。從上下文來(lái)看DDT的特點(diǎn)是沒(méi)有分辨性：它既能殺死有害的昆蟲又能殺死有益的昆蟲。

　　8.but-and/so。本句的兩個(gè)意群的關(guān)系是順接，不是轉(zhuǎn)折，因此應(yīng)選用順接的連詞，如and和so等。

　　9.^series-a。series這個(gè)名詞屬于單數(shù)復(fù)數(shù)同形，它經(jīng)常與a和of構(gòu)成詞組a series of表示“一系列的”。

　　10.which-where。from這個(gè)介詞后面應(yīng)接一個(gè)介詞表具體方位，因此這里只能用表方位的副詞where。