摘要：
现在完成时:只提起已发生的动作（事实）及其影响,不说明动作发生时的具体情况.cf.Haveyouhadyourlunch?Whatdidyouhaveforlunch?Ihavee... 现在完成时:只提起已发生的动作（事实）及其影响,不说明动作发生时的具体情况.
cf. Have you had your lunch?
What did you have for lunch?
I have ever been to the Great Wall,_and_I went there last summer with my father.
注:现在完成时表达的动作常具有反复性,故下面一句是错的:
Have you seen the six thirty`s news program?
应改为:
Did you see the six thirty`s news program?
四、现在完成进行时主要用于:表示过去开始的某一动作一直持续到现在,以至延伸到将来,它强调动作延续时间之长久.
e.g. I`ve been writing an article. 我一直在写一篇文章.（还在写）
cf. I`ve written an article. 我写了一篇文章.（已写完）
It has been raining these days. 这些天一直在下雨.
五、过去完成时
1 、过去完成时是一个相对时态,表示过去的过去,只有在两个过去发生的动作相比较时才可显示出来.
e.g. As soon as we got to the station, the train had left.
