碩士在職研究生已經無法滿足部分高追求在職人員的需求，越來越多的在職人員選擇報考在職博士繼續學習。以下是中國在職研究生招生信息網的老師整理的部分考博英語改錯練習題，有需要的考生可以參考練習。

　　Changes in climate that had already taken place are manifested __1__from the decrease in extent and thickness of Arctic sea ice, perma- __2__frost thawing, coastal erosion, changes in ice sheets and ice shelves, altered distribution and abundance of species. __3__Nowadays snows melt earlier in the springtime. Lakes, rivers and bogs freeze much more later in the autumn. Reindeer herding __4__becomes more difficult so the ice is weak and may give way. __5__Nowadays winters are much colder than they used to be. __6__Occasionally during winter time it rains. We never expected this;we could not be ready for this. It is very strange. The cycle of the yearly calendar has been disturbed greatly. Warming over northern land areas has been very greater than elsewhere in the world. The __7__changes are due to human modification of the concentration of greenhouse gases during the 20th century, leading quite directly to the projections the Artic will warm by several times as much during the __8__

　　21st century as it did during the 20th century. The amplified warming in Arctic, in turn, directly contributes to overall global warming, as __9__well as cause changes that create impacts over the rest of the globe. __10__

　　答案及解析:

　　1.had-have

　　這里沒有語境表明這個動作或者狀態發生在過去某個時間點以前，所以用過去完成體不合適。

　　2.from-in

　　manifest something in something 意思是“在……方面表現出來”。例如：

　　His frustration manifested itself in his silence and inactiveness。

　　3.^altered-and

　　這里要看出并列的幾個名次詞組是 extend and thickness…、permafrost thawing、coastal erosion、changes in ice sheets and ice shelves、altered distribution and abundance of species，三個斜體的and并不是連接這幾個并列項的，所以必須在最后一項altered distribution and abundance of species前加上并列連詞and。

　　4.more-/

　　later本身已經是比較級，不用再加more。

　　5.so-as/since

　　這里要理清主從句的因果關系，從上下文看，應該說“冰層變薄”是因，“放牧馴鹿變得困難”是果，所以應該把so 改成as或since。

　　6.colder-warmer

　　文章談的是氣候變暖問題。“冬季變冷”顯然是與整個文章的邏輯不符。

　　7.very-/

　　very不修飾形容詞或者副詞的比較級。(覺得這里把very 改為much 也沒問題)

　　8.projections^-that

　　projections后面的從句是同位語從句，同位語從句的引導詞that不可以省略。

　　9.^Arctic-the

　　“北極”Arctic前要加定冠詞。

　　10.cause-causing

　　as well as相當于介詞，其后不直接跟動詞，應該是名次或動詞-ing分詞。