1)现在完成时说明的是现在的情况,是现在时态,因此不能和表示过去时间的状语如yesterday,1asr month,three years ago,in l960等连用。这些时间状语只能和过去时态连用,表示过去的动作。但现在完成时可和表示过去时间的副词just和before连用。如:
He has just come.他刚到。
We have seen the movie before,我们以前看过这个电影。
2)现在完成时常和表示不确定的时间的副词already,never,ever,always,yet,not...yet,often等连用。如:
Have you ever been in a plane? 你坐过飞机吗?
The new books have not arrived yet.新书还没有到。
The Xisha lslands have always been Chinese territory.西沙群岛一直是中国的领土。
Have you heard from him yet? 你接到他的信了吗?
They have already finished their experiment.他们已经做完试验了。
Many westerners have never seen a giant panda.许多西方人从没见过大熊猫。
We have often been to the Summer Palace.我们常到颐和园去玩。
3)现在完成时可以和包括"现在"在内的时间状语连用,如now,today,this month,this year等。如:
We have planted many fruit trees this year.我们今年种了很多果树。
Have you seen Benny today? 你今天见到本尼了吗?
We've had a lot of rain this summer.今年夏天雨下得很多。
但如说话人所感兴趣的只是在这段时间内发生了某一动作,而不是这一动作与现在的关系时,须用过去时态。如:
The conference opened this month.会议是本月开幕的。
Their farm set up a pumping station this year.他们农场今年新修了一个抽水站。
现在完成时可和疑问副词where,why,how连用,但通常不和疑问副词when连用
(when一般只与过去时态连用)。如:
Where have you been? 你去哪儿了?(询问经过情况。如说Where did you go?则只问地点)
Why have you turned off the radio? 你干吗把收音机关了?(强调和现在的关系,意即收音机关着。如说Why did you turn off the radio?则强调关收音机这一过去的动作。)