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英語語法大全|現(xiàn)在完成時(shí)的結(jié)構(gòu)和用法

（一）基本結(jié)構(gòu)

現(xiàn)在完成時(shí)的句子結(jié)構(gòu)一般為：

主語+have/has+過去分詞+其他成分

如：

We have already had lunch.

He has been away for a week.

（二）主要用法

1、表示過去發(fā)生并且已經(jīng)完成的動(dòng)作對(duì)現(xiàn)在造成的影響或結(jié)果。此時(shí)，常和謂語動(dòng)詞一起使用的副詞有already、just、never、ever、yet等。如：

They have already come back from the museum.

She has already finished her homework.

2、表示過去發(fā)生的動(dòng)作持續(xù)到現(xiàn)在，并且有可能會(huì)繼續(xù)持續(xù)下去。此時(shí)，常和謂語動(dòng)詞一起使用的標(biāo)志性詞語主要有for和since，而且此時(shí)的謂語動(dòng)詞往往是持續(xù)性動(dòng)詞（如stay、keep、wait等）。如：

I have lived here for ten years.

He has kept the clavichord since thirty years ago.

3、表示從過去某一時(shí)間到說話時(shí)這段時(shí)間中反復(fù)發(fā)生的動(dòng)作。此時(shí)，常和謂語動(dòng)詞一起使用的主要是表頻度的副詞often、always、seldom、never等，以及表次數(shù)的單詞或短語（如once、twice、three times）。如：

You have never listened to me like this before.

She has ever been to France.

They have visited the Summer Palace many times.

（三）動(dòng)詞的過去分詞

1、規(guī)則變化

其變化規(guī)則與動(dòng)詞的一般過去時(shí)基本相同，主要是在詞尾加-ed或-d。具體的有：

1）直接加-ed。如：worked、played。

2）以不發(fā)音的e結(jié)尾的動(dòng)詞后加-d。如：lived、danced。

3）以輔音字母加y結(jié)尾的動(dòng)詞后改y為i，再加-ed。如：studied、cried。

4）以重讀閉音節(jié)結(jié)尾的動(dòng)詞后，雙寫最后一個(gè)輔音字母再加-ed。如：stopped、patted。

2、不規(guī)則變化

如果結(jié)合動(dòng)詞的過去式，動(dòng)詞的過去分詞的不規(guī)則變化中，又有一些相對(duì)的規(guī)則現(xiàn)象。如：

1）AAA型。如：put put put；read read read。其中，read的過去式和過去分詞雖然拼寫時(shí)一樣的，但其發(fā)音與原形不同，ea不再讀作[i?]，而是[e]。

2）AAB型。如：beat beat beaten 

3）ABB型。如：keep kept kept；sit sat sat

4）ABC型。如：lie lay lain；drink drank drunk

5）ABA型。如：run ran run；come came come

（四）標(biāo)志性詞語

1、副詞already、just、never、ever、yet等。如：

She hasn't arrived in Scotland yet.

They have just left for Shanghai.

2、for和since。for+一段時(shí)間，since+具體時(shí)間。如：

He has learned Italian for five months.

He has learned Italian since five months ago.

3、so far和up to/till now。表示“迄今為止”。如：

So far, no one has heard any news about her.

She has read fifty books up to now.

4、recently、lately等表示“最近；最新”的副詞和形容詞。如：

I've met her on several occasions recently.

He hasn't had enough sleep lately.

5、in the past/last+一段時(shí)間，表示“在過去的...時(shí)間里”。如：

In the past few years, new buildings have sprung up all over Beijing.

He had aged rapidly in the last few months.

6、次數(shù)。如：

I've tried many times, but there's no way.

He has been there at least twice.

（五）have been to/have gone to/have been in

1、have been to

表示“去過已回”。句子主語就在現(xiàn)場(chǎng)。如：

They have been to Rome many times.

She has been to Shanghai more than once.

2、have gone to

表示“去了未回”。句子主語不在現(xiàn)場(chǎng)。如：

Jerry has gone to Hangzhou.

Mary has gone to Finland.

3、have been in

表示“一直待在某地”。如：

We have been in Beijing for five weeks.

They have been in China since 2012.

（六）短暫性動(dòng)詞和延續(xù)性動(dòng)詞

所謂短暫性動(dòng)詞主要是指一旦發(fā)生馬上就結(jié)束的動(dòng)作，也叫瞬間動(dòng)詞，如die、marry、leave等。而延續(xù)性動(dòng)詞主要是指可以一直持續(xù)進(jìn)行的動(dòng)作，也叫持續(xù)性動(dòng)詞，如learn、live、talk等。

兩類動(dòng)詞都可以用于現(xiàn)在完成時(shí)，但是短暫性動(dòng)詞不能與表示一段時(shí)間的時(shí)間狀語連用。此時(shí)，需要把短暫性動(dòng)詞改為相應(yīng)的表狀態(tài)的動(dòng)詞或短語。如：

錯(cuò)誤：He has died for ten years.

正確：He has been dead for ten years.

錯(cuò)誤：She has married him since five years ago.

正確：She has been married to him since five years ago.

（七）句型轉(zhuǎn)換

因?yàn)椤癶ave/has done”中的have/has是助動(dòng)詞，所以在進(jìn)行句型轉(zhuǎn)換中要注意不需要再另外借助助動(dòng)詞do/did/does，而是直接借用have/has。如：

肯定句：He has lived here for the last few years.

否定句：He hasn't lived here for the last few years.

一般疑問句：Has he lived here for the last few years?

特殊疑問句：How long has he lived here?  （劃線部分為for the last few years）