一、現(xiàn)在完成時(shí)

1、表示過去開始并持續(xù)到現(xiàn)在的動(dòng)作。（動(dòng)詞必須是持續(xù)動(dòng)詞）

China?has changed a great deal in the past 20 years.?

2、強(qiáng)調(diào)過去動(dòng)作對(duì)現(xiàn)在的影響和結(jié)果。（可以使用非持續(xù)動(dòng)詞）

Where have you put the dictionary? I can't find it anywhere.

3、表示反復(fù)性或習(xí)慣性。常常與often, frequently及表示次數(shù)之類的詞連用。

I have watched him appear on TV several times.

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二、現(xiàn)在完成進(jìn)行時(shí)

1、表示過去某時(shí)開始的動(dòng)作一直持續(xù)到現(xiàn)在，并在持續(xù)期間內(nèi)不斷進(jìn)行著。

I have been working for five years.?

It has been raining since last Friday.

2、表示重復(fù)的動(dòng)作。

Jim has been ringing John every night for the last week.

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三、區(qū)別

1、現(xiàn)在完成時(shí)表示動(dòng)作業(yè)已完成，而用現(xiàn)在完成進(jìn)行時(shí)談?wù)撐赐瓿傻膭?dòng)作。

I have painted this room.（I’ve finished painting it.）

I have been painting this room.（I haven’t finished painting it.）

2、現(xiàn)在完成時(shí)關(guān)注動(dòng)作的結(jié)果，尤其是談到數(shù)字或數(shù)量時(shí)；而現(xiàn)在完成進(jìn)行時(shí)關(guān)注動(dòng)作本身，特別是解釋動(dòng)作可見的結(jié)果時(shí)。

He’s run three miles. (the result: He’s covered the distance of three miles.)

He’s been running for an hour. (the activity and its consequences: this is what he’s been doing for the last hour and why he is exhausted now.)

3、現(xiàn)在完成進(jìn)行時(shí)表示重復(fù)的動(dòng)作時(shí)，不能同表示具體數(shù)字的詞并用。

I’ve posted a dozen postcards, but received none.

I’ve read this book several times.

I’ve been posting postcards since early December.

4、現(xiàn)在完成進(jìn)行時(shí)帶有較為強(qiáng)烈的感情色彩。

You have been disturbing me.

5、許多狀態(tài)動(dòng)詞不能用完成進(jìn)行時(shí)。

I’ve known that for a long time.?

The strike has lasted six months.

6、有少數(shù)動(dòng)詞用兩種時(shí)態(tài)都可以，但若強(qiáng)調(diào)時(shí)間長(zhǎng)度時(shí)用完成進(jìn)行時(shí)較好。

They have been working this term.

They?have worked very well this term.