题目内容
10．Because it _________ every day，the window is very clean．（ ）| A． | cleaned | B． | will clean | C． | was cleaned | D． | is cleaned |
分析 因为每天都清洗，所以那扇窗户很干净．
解答 答案：D．
首先根据时间状语every day，判断句中的谓语动词是经常性反复性的动作，所以用一般现在时，主语it（the window）是动作clean的承受者，所以用被动语态，一般现在时被动语态的构成是：主语+am/is/are+动词的过去分词，主语是it，be动词用is，clean的过去分词是cleaned，故选D．
点评 本题考查时态和语态．每个时态都有标志词，熟记这些标志词是做题的关键．在没有时间状语的情况下可以根据语境来对时态做出判断．判断语态的关键则是观察主语是谓语动词的执行者还是承受者．
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