在表達一個在過去開始而現(xiàn)在仍在繼續(xù)或剛剛結(jié)束的動作時,某些動詞既可以用現(xiàn)在完成時,也可以用現(xiàn)在完成進行時。這樣的動詞有expect,hope,learn,lie,live,look,rain,sleep,sit,snow,stand,stay,study,teach,wait,want,work等.
How long have you learnt English?你學習英語多久了?
How long have you been learning English?(譯文同上。)
He has slept for ten hours.他已經(jīng)睡了十個小時了。
He has been sleeping for ten hours.(譯文同上。)
It has snowed for a long time.雪下了好長時間了。
It has been snowing for a long time.(譯文同上。)

沒有進行式的動詞不可能有這樣的用法,即現(xiàn)在完成進行時不能代替以下例句中的現(xiàn)在完成時:
They’ve always had a big garden.他們一直有一座大花園。
How long have you known that?你知道這事多久了?
He’s been in hospital since his accident.他從發(fā)生事故之后,一直在醫(yī)院里。

注意:現(xiàn)在完成進行時可以和時間短語連用,也可以不連用,這一點就有別于現(xiàn)在完成時,因為后者與像for six days,since June,never等一些時間短語連用才能表示這類動作。不用這些時間狀語時,現(xiàn)在完成時指的是完成了的一個動作。

B 用現(xiàn)在完成時表示的反復的動作,有時可以作為連續(xù)的動作用現(xiàn)在完成進行時表示:
I’ve written six letters since breakfast.早飯后我已經(jīng)寫了六封信。
I’ve been writing letters since breakfast.早飯后我一直在寫信。
I have knocked five times.I don’t think anyone’s in.
我敲了五次門。我想屋里沒有人。
I’ve been knocking.I don’t think anybody’s in.

我一直在敲門。我想屋里沒有人。
注意:現(xiàn)在完成進行時表示一種看來似乎是不間斷的動作,所以提到做一件事的次數(shù)或一共做了多少事情時,不能用現(xiàn)在完成進行時。

C 用現(xiàn)在完成時表達的單一動作和用現(xiàn)在完成進行時表達的動作是有區(qū)別的:
(a)I’ve polished the car.我擦了車。意指這件事已經(jīng)結(jié)束了。
(b) I’ve been polishing the car.我在擦車來著。

意指過去一小時我就是這樣度過的,而不一定指動作已結(jié)束。注意:用現(xiàn)在完成進行時表示單一動作時,這一動作持續(xù)到說話的時間或者接近這一時間為止:
He’s been taking photos.
他一直在拍照。(他大概手里正拿著照相機。)
He has taken photos.
他拍過相片。(這件事可能是也可能不是最近發(fā)生的。)

例句:

1.He has been speaking English since he came to the USA.
(現(xiàn)在完成進行時,強調(diào)動作的連續(xù)性。

2.Complete these sentences with the present continuous form of the verbs given in the brackets, changing the word order where necessary.
用括號中所給的動詞的現(xiàn)在進行時完成句子,必要時變化詞序。

t perfect ph.1. 【語】現(xiàn)在完成時,2. 【語】現(xiàn)在完成時的

4.During the procession, the microprocessor finished the processing procedure.
在隊伍行進時,微處理器完成了加工過程.

execute and complete certain Works and remedy any defects therein as therein mentioned in conformity with the provisions of the said Contract.
去實施并完成某項工程,并在工程出現(xiàn)任何缺陷時,按上述合同中有關(guān)條款規(guī)定進行修補。

6.Installation of applications on this computer is complete. The computer will now restart.
已完成在此計算機上進行的應用程序安裝。計算機現(xiàn)在要重新啟動。

7.During Iteration Planning, the Customer presents the features desired for the next two weeks.
在進行迭代計劃時,客戶演示下兩周內(nèi)希望完成的特性。

8.Change the following sentences into the Present Continuous Passive Voice.
把下列句子變成現(xiàn)在進行時的被動語態(tài)。

9.`I have finished' is an example of the present perfect.
“我已經(jīng)完成了”是現(xiàn)在完成時態(tài)的一個例句。

10.a perfective tense used to express action completed in the present.
一種用來表達現(xiàn)在已經(jīng)完成的動作的完成時態(tài)。

11.And will learn The simple past tense, The present perfect tense, The past perfect tense as well as The future tense.
這個學期,我們學到了過去時,現(xiàn)在完成時,過去完成時和將來時等。

12.Cleanup of merge meta data cannot be performed while merge processes are running. Retry this operation after the merge processes have completed.
合并進程運行時無法執(zhí)行合并元數(shù)據(jù)的清除。請在合并進程完成后重試此操作。

13.Download Complete. Extracting Files.
下載完成。正在對文件進行解壓縮。

14.The work is in hand and will soon be completed.
這工作在進行中, 不久即可完成.

15.The work is in hand and will soon be finished .
工作在進行中,很快就會完成。

16.The work be In hand and will soon be completed
這工作在進行中, 不久即可完成

17.The request has been accepted for processing, but the processing has not been completed.
已接受請求,正在進行處理,但尚未完成。

18.Queen Mary's joint degrees will be taught entirely in China.
女王瑪莉雙學位將完成在中國進行。?