在GMAT語法考試中經(jīng)常會出現(xiàn)由于連接詞的改變而導致句意改變的題目，如果對于連接詞掌握不好的話，很容易出現(xiàn)誤判，今天小編就給大家介紹下GMAT語法連接詞中while與but的區(qū)別，快來了解一下吧！
while引導的從句：
意思是“當…時”，放句首或句中
意思是“轉(zhuǎn)折對比contrast”時，多放在句中，也可以放在句首。
while表示對比概念的時候，兩個事物要是同時發(fā)生。
意思是“雖然、盡管”(讓步)時，多放在句首。(=although)
表示條件,意為"只要",其意思和用法相當于as long as。while可位于句首,也可位于句中。
真題解析
真題1：
After several years of rapid growth,the healthy care company became one of the largest health care providers in the metropolitan area,while it then proved unable to handle the increase in business,falling months behind in its payment to doctors and hospitals.
A.while it then proved unable to handle the increase in business,falling months behind in its payment to
B.while it then proved unable to handle the increase in business and fell months behind in its payment to
C.but then it proved unable to handle the increase in business,falling months behind in its paying
D.but then proving unable to handle the increase in business,falling months behind in paying
E.but then proved unable to handle the increase in business,falling months behind in paying
翻譯：
幾年的飛速發(fā)展之后，健康護理公司成為這個大城市最大的健康公司之一，然而之后卻不能很好地處理快速成長的事業(yè)，好幾個月沒有付醫(yī)生和整個醫(yī)院工資
句式：
the company became one of the largest providers,but then proved unable to handle sth.,falling months behind in panying
思路：
考察轉(zhuǎn)折
選項：
A.即便表示轉(zhuǎn)折對比，while也有"at the same time"的含義在里面，與then矛盾，并讓句意變成了the health care company expanding and falling是同時發(fā)生的，但是實際上應(yīng)該是先became largest，然后再fell;
B.同B，并且fell和proved形成并列，邏輯不對;
C.前面的it多余，可以省略(effctiveness);in its paying，使得paying從動詞變成了動名詞，不簡潔，prep.+one's+doing往往是不簡潔的。paying這個動作就是the health care company執(zhí)行的，所以不用加上its;
D.but要連接兩個句子或謂語，proving改變了邏輯;
E.正確。
真題2:
Building large new hospitals in the bistate area would constitute a wasteful use of resources,on the basis of avoidance of duplicated facilities alone.
A.on the basis of avoidance of duplicated facilities alone
B.on the grounds of avoiding duplicated facilities alone
C.solely in that duplicated facilities should be avoided
D.while the duplication of facilities should be avoided
E.if only because the duplication of facilities should be avoided
翻譯：
如果僅僅因為是這些設(shè)施的重復應(yīng)該被避免，那么在B這個區(qū)域建又大又新的醫(yī)院將會是一種資源的浪費。
句式：
Building X would constitute a wasteful use of Y,(modifier).
思路：
通過意思來理解句子意思;前面說了一件事，后面解釋了一個原因。
選項：
A.'on the basis of x'這個短語中會默認為X已經(jīng)存在了,但是A沒有出現(xiàn)問題，所以選擇錯誤;介詞兩個一般會造成修飾錯誤;
B.avoiding duplicated facilities語義邏輯錯誤，文章強調(diào)的是避免重復而并非避免工廠;強調(diào)重心發(fā)生變化;avoid的邏輯主語錯誤;
C.avoiding duplicated facilities語義邏輯錯誤，文章強調(diào)的是避免重復而并非避免工廠;強調(diào)重心發(fā)生變化;avoid的邏輯主語錯誤
D.同樣改變句子意思，原本是通過一個修飾成分說明為什么building是不好的;但是WHILE卻出現(xiàn)了轉(zhuǎn)折的意思;
E.正確。
真題3：
Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants,having gone virtually unregulated since they were developed more than 50 years ago.
A.while at the same time they have introduced some 100,000 dangerous chemical pollutants,having
B.while at the same time introducing some 100,000 dangerous chemical pollutants that have
C.while they have introduced some 100,000 dangerous chemical pollutants at the same time,which have
D.but introducing some 100,000 dangerous chemical pollutants at the same time that have
E.but at the same time introducing some 100,000 dangerous chemical pollutant,having
翻譯：
工業(yè)化的殺蟲方法提高了人們的生活水平而于此同時這些方法也引入了一些化學污染物，這些化學污染物沒有得到有效的管理。
句式：
Industrialization and modern methods…h(huán)ave improved…while introducing…
思路：
While和but的區(qū)別，一個可以加動名詞，一個不可以;還有代詞指代的問題。
選項：
A.Having修飾主語IM methods，邏輯語義錯誤，應(yīng)該修飾污染物;整個句子中的兩個代詞they指代對象不一致，劃線部分they沒有指代對象，未劃線部分的they指代的是pollutants;
B.正確;
C."introduced 100,000 dangerous chemical pollutants at the same time"表示的是這么多化學物質(zhì)被同時引入;但是邏輯語義只是強調(diào)了污染物被引入是一個什么樣的影響;整個句子中的兩個代詞they指代對象不一致，劃線部分they沒有指代對象，未劃線部分的they指代的是pollutants;
D.Introducing和have improved不平行;but需要前后平行，while不需要;
E.having gone…分詞結(jié)構(gòu)有作伴隨狀語修飾have introduced的歧義，而不是作pollutants的定語。
