摘要：3．现在完成时 (1)现在完成时用来表示对目前状况仍有影响的.刚刚完成的动作(常与yet.already.just连用).或者过去某一时刻发生的.持续到现在的情况.例如: 1)I have just finished my homework. 2)Mary has been ill for three days. (2)常与现在完成时连用的时间状语有:since, for, during, over等引导出的短语,副词already, yet, just, ever, now, before, often, lately, recently等,状语词组this week , so far, up to now, many times, up to the present等.例如: 1)I haven’t been there for five years. 2)So far, she hasn’t enjoyed the summer vacation. 3)There have been a lot of changes since 1978. (3)完成时态可用在下列结构中: This the first time +定语从句,This the only + n +定语从句,This +形容词最高级+ n +定语从句.如果主句的谓语动词是一般现在时.从句的谓语动词通常用现在完成时,如果主句谓语动词是一般过去时.从句谓语动词通常用过去完成时.例如: 1)This is one of the rarest questions that have ever been raised at such a meeting. 2)There was a knock at the door. It was the second time someone had interrupted me that evening.

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