e.g. Have you had lunch? Yes, I have. I’ve just had it. 你吃过午饭没?有，吃过了，我刚刚吃的。(影响及结果：我现在饱了，不需要了)

He has gone to Beijing. 他已经去北京了。(影响及结果：他人现在不在这里了)

该用法常already(已经), never(从不), ever(曾经), yet(仍然), just(刚刚), before(以前)等副词(作状语)连用。

①already, just, ever, never常用于助动词之后，实义动词之前。 already, just多用于肯定陈述句。

e.g. She has already finished her work. 她早已干完了活。

Would you like to go to see the film? No, I’ve seen it already.不，我已经看过了。(already偶尔会出现于句末)

They have just won a game. 他们刚刚赢了一场比赛。

有时already可以用于疑问句，表示期待肯定回答，或表示惊讶、意外。

e.g. Have you finished reading the book already? 你真的已经读完这本书了?(表示惊讶)

ever多用于疑问句，问初次经历。

e.g. Have you ever spoken to a foreigner? 你跟外国人讲过话吗?(问初次经历)

never多用于否定陈述句(注：本身表示否定意义)

e.g. He has never done such a thing, has he? 他从来没有做过这样的事，不是吗?(否定)

②yet一般用于疑问句(已经)或否定句(还)，常位于句末。

e.g. Have you got ready yet? 你已经准备好了吗? He hasn’t finished his homework yet. 他还没完成作业。

③before一般位于句末。

e.g. I have never seen the film before. 以前我从未看过那部电影。 现在完成时的第一种用法常与以上的副词连用，因此这些词有时可以作为现在完成时的标志词。

(2) 现在完成时的第二个基本用法表示过去已经开始，持续到现在的动作或状态。该用法常和表示过去某一时刻延续到现在的一段时间的状语连用。

①与for +一段时间连用，表示多久。

e.g. He has learned English for two years. 他已经学习两年英语了。

I have been here for three days. 我在这里已经3天了。

②与since +时间(起点)连用，表示自…以来。

e.g. His father has worked in that factory since 1991. 他爸爸自1991年以来都在这家工厂工作。

I’ve had a cold since last Friday. 自上星期五起我就感冒了。

③与since +一段时间+ ago连用，表示自…以前就…。

e.g. Jim has waited there since half an hour ago. 吉姆自半个小时前就已经在那里等候了。

He has stayed here since three weeks ago. 他在这儿已呆了三个星期。

④与since +从句(从句用一般过去时)连用，表示自某事发生后就一直…。

e.g.The Greens have lived in Beijng since they came to China. 格林一家自从来到中国后就一直住在北京。

I’ve known her since I came to work here. 自从我来这里工作就认识他了。

(3) 现在完成时的第三个基本用法表示到现在为止这一时期中多次动作的总和或所做过的工作的量的积累。

e.g. I have been to Beijing twice. 我去过北京两次。

We’ve learnt five English songs this year. 今年我们学了五首英语歌曲。

How many pages of the book have you read? 这本书你读了多少页了?

4、延续性与非延续性动词在现在完成时态中的使用。

(1)有一些动词是瞬间动词，也叫非延续性动词，这些动词一发生就结束了，常见的有：come, go, arrive, reach, leave, begin, start, buy, join, die, borrow, get up, become, open, stop等。这些动词虽然可以用于现在完成时(说明某个动作的结果还存在)，但由于它们不能延续，因此不能跟表示一段的时间状语连用。(也即现在完成时的第二个基本用法中不能使用非延续性动词)。

e.g. Jim has come back. (正) 吉姆已经回来了。

Jim has come back for a month. (误) come back的动作不能延续一个月，因此错误。

(2)瞬间动词不可以用于有段时间的现在完成时态中，因此，若要解决这一问题，就应把它改为相应的延续性动词或短语，主要有以下几种：

①用相应的延续性动词

如：buy → have borrow → keep come/go/become → be put on → wear catch a cold → have a cold ②转换成be+名词

如：join → be a member of go to school → be a student ③转换成be+形容词或副词

如：die → be dead leave → be away begin → be on finish → be over fall asleep — be asleep open → be open get up → be up close → closed ④转换成be+介词短语

如：come to/go to/arrive in (at)/get to/reach …→ be in/at… join the army → be in the army(军队)

e.g. I have borrowed the book. 我已经借了那本书。

I have kept the book for two days. 我已经借那本书两天了。

Jim has joined the band. 吉姆已经加入那乐队了。

Jim has been a member of the band for a month. 吉姆已经加入那个乐队一个月了。

His grandfather has died. 他祖父已经死了。

His grandfather has been dead for 2 years. 他祖父已经死了两年了。

My father has arrived in China. 我父亲已经到达中国了。

My father has been in China for a week. 我父亲已经在中国一个星期了。

(3)在否定句中，非延续性动词也可以与时间段连用。

e.g. I haven’t borrowed books from the library since last year. 自去年以来我就没有在图书馆借过书。

Jim hasn’t come back for a year. 吉姆已有一年没回来了。

6、现在完成时的几种常见的句型转换。

现在完成时可以转化成一般过去时，还可以转化成“It is/has been +时间段+since从句(用一般过去时)”等句型。

e.g. Jim has been back for a month. 吉姆已经回来一个月了。 = Jim came back a month ago. 吉姆一个月前就回来了

= It is/has been a month since Jim came back. 自吉姆回来已经有一个月了。 = A month has passed since Jim came back. I have kept the book for two days. = I borrowed the book two days ago.

= It is / has been two days since I borrowed the book. = Two days has passed since I borrowed the book.

7、现在完成时和一般过去时的区别：

现在完成时强调的是过去的动作对现在的影响，它和现在有密切的联系。现在完成时经常会出现下列的标志词。

如：already, yet, just, ever, never, several times, before, so far, for +时间段, since +时间点或从句等。一般过去时强调的是动作发生的时间、地点，不涉及对现在的影响，所以凡含有表示过去的时间状语的句子，都必须用一般过去时，不能用现在完成时。返回搜狐，查看更多