题目内容
20.In the past decades,sea ice in the Arctic as a result of global warming.( )A. | has been melting | B. | had melted | ||
C. | melted | D. | is melting |
分析 在过去的几十年,由于全球变暖导致北极的冰川迅速融化.
解答 答案:A.
考查现在完成进行时.句中的时间状语"over the past decades",谓语动词用现在完成时或现在完成进行时.根据句意冰川融化从过去开始一直持续到现在,并且还会继续融化.这是用现在完成进行时.所以选A.
点评 本题考查现在完成进行时.现在完成进行时表示某动作从过去某个时间开始,一直持续到现在,并且还有可能继续持续下去,其形式为have/has+been+doing.
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