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帮我看看这是介绍什么时态,现在完成时还是现在完成进行时

来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:英语作业 时间:2024/05/31 18:34:37
帮我看看这是介绍什么时态,现在完成时还是现在完成进行时
(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(常与for,since连用).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 (morning,month,year),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 (That,It) is (was) the first (second…) time +定语从句;This (That,It) is (was) the only (last) + n +定语从句;This (That,It) is (was) +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.
帮我看看这是介绍什么时态,现在完成时还是现在完成进行时
现在完成时
再问: 为什么?现在完成进行时才用hava been doing 不是吗?
再答: 这里没有讲have been doing 丫。。。