现在完成时预先在完成进行时的标志词各是什么？

1.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(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 knoc