【文章內(nèi)容簡介】 cting us the next 。b)表示在過去某一時間之后即將或按計劃進行的動作。如：He said he could not e because he would be haying a ，因為要開會。 現(xiàn)在完成時（Present perfect tense）表示動作發(fā)生在過去，但與現(xiàn)在情況有關(guān)系，即用一個發(fā)生在過去的動作來說明現(xiàn)在的情況。現(xiàn)在完成時由動詞have (has) + 過去分詞構(gòu)成。 現(xiàn)在完成時的基本用法1)表示動作到現(xiàn)在為止已經(jīng)完成或剛完成，漢語常用了或過來表示。如：I have finished my 。We have set up many new factories in this 。She has read all these 。2)動作在過去完成，表示經(jīng)驗或結(jié)果。漢語常用過來表示。如：Have you ever seen the play The Doll39。s House? 你看過話劇《傀儡家庭》嗎?Yes，I have seen it 。I have learnt to 。The man has lived in 。[注] 注意be在下面句子中的意義。如：Where have you been? －I39。ve been to the ?到實驗室去了。Have you ever been to Hangzhou? ―No，I39。ve never been ?沒到過。How have you been?－I39。ve been well thank ?謝謝你，我近來很好。 現(xiàn)在完成時與過去一般時的區(qū)別現(xiàn)在完成時和過去一般時都表示在過去完成的動作，但現(xiàn)在完成時強調(diào)這一動作與現(xiàn)在的關(guān)系，如對現(xiàn)在產(chǎn)生的結(jié)果、影響等，而過去一般時則表示動作發(fā)生在過去，一般不表示和現(xiàn)在的關(guān)系。試比較：1)I have lost my 。(意即還沒找到，現(xiàn)在我沒有筆用。)She lost her pen yes 。(筆是昨天丟的，現(xiàn)在找到與否，沒有說明。)2)I have been to the Agricultural 。(強調(diào)我知道它的內(nèi)容)I went to the Agricultural Exhibition last 。(只說明我上周參觀過展覽會這件事)3) Who has opened the door? 誰把門開了?(現(xiàn)在門還開著)Who opened the door? 誰開的門?(指過去，與現(xiàn)在無關(guān)。現(xiàn)在門是關(guān)著還是開著，沒有說明。)4) A：Have you had your lunch? 你吃過年飯沒有?(意即你現(xiàn)在不餓嗎?)B：Yes，I 。(意即我現(xiàn)在飽了，不要再吃了。)A：When did you have it 你什么時候吃的?(說話人感興趣的是吃這一動作發(fā)生在什么時候。)B：I had it about half an hour 。 現(xiàn)在完成時的其他用法1)還可表示動作發(fā)生在過去，并且一直延續(xù)到現(xiàn)在，甚至還可能繼續(xù)延續(xù)下去。這時常和since所引導(dǎo)的短語或從句或for引導(dǎo)的短語連用(for有時可以省去)。How long have you been in Beijing ? －I have been in Beijing for four ?我在北京呆了四年。Isaac39。s father has been a school teacher since 1968. 艾薩克的父親從一九六八年以來就當(dāng)教師。We haven39。t had a vacation for a long 。Three years have passed since we left 。[注]但在下面的句子中，主句的謂語動詞可以用現(xiàn)在一般時。如：It is three years since I began to work on the state 。(美國英語用has been，下例同此)It39。s a long time since I saw you 。2)在條件、時間狀語從句中表示將來完成的動作。I39。ll go with you when I have finished my home work，我做完作業(yè)后就和你一塊去。We39。ll wait here until you have Written the 。Perhaps I39。ll know more English after I have learnt it for two ，懂的英語或許就會多些了。 現(xiàn)在完成時的時間狀語問題1)現(xiàn)在完成時說明的是現(xiàn)在的情況，是現(xiàn)在時態(tài)，因此不能和表示過去時間的狀語如yesterday，1asr month，three years ago，in l960等連用。這些時間狀語只能和過去時態(tài)連用，表示過去的動作。但現(xiàn)在完成時可和表示過去時間的副詞just和before連用。如：He has just 。We have seen the movie before，我們以前看過這個電影。2)現(xiàn)在完成時常和表示不確定的時間的副詞already，never，ever，always，yet，not...yet，often等連用。如：Have you ever been in a plane? 你坐過飛機嗎?The new books have not arrived 。The Xisha lslands have always been Chinese 。Have you heard from him yet? 你接到他的信了嗎?They have already finished their 。Many westerners have never seen a giant 。We have often been to the Summer 。3)現(xiàn)在完成時可以和包括現(xiàn)在在內(nèi)的時間狀語連用，如now，today，this month，this year等。如：We have planted many fruit trees this 。Have you seen Benny today? 你今天見到本尼了嗎?We39。ve had a lot of rain this 。但如說話人所感興趣的只是在這段時間內(nèi)發(fā)生了某一動作，而不是這一動作與現(xiàn)在的關(guān)系時，須用過去時態(tài)。如：The conference opened this 。Their farm set up a pumping station this 。 現(xiàn)在完成時可和疑問副詞where，why，how連用，但通常不和疑問副詞when連用(when一般只與過去時態(tài)連用)。如：Where have you been? 你去哪兒了?(詢問經(jīng)過情況。如說Where did you go?則只問地點)Why have you turned off the radio? 你干嗎把收音機關(guān)了?(強調(diào)和現(xiàn)在的關(guān)系，意即收音機關(guān)著。如說Why did you turn off the radio?則強調(diào)關(guān)收音機這一過去的動作。) 助動詞1. 助動詞的形式與作用1)英語常用的助動詞(auxiliary verb)有shall，will，should，would，be，have，do等。助動詞一般無詞義，不能單獨作謂語動詞。助動詞在句中的作用，在于幫助構(gòu)成各種時態(tài)、語態(tài)、語氣、否定和疑問結(jié)構(gòu)等。如：China has entered a great new era. 中國已進入了一個偉大的新時期。(幫助構(gòu)成完成時態(tài))Some boys are playing on the grass. 一些男孩正在草地上玩。 (幫助構(gòu)成進行時態(tài))Mother is written by Gorky. 《母親》是高爾基寫的。 (幫助構(gòu)成被動語態(tài))We Shall have the football match if it does not ，我們就賽足球。(幫助構(gòu)成將來時態(tài)和否定結(jié)構(gòu))Do you see my point? 你明白我的意思嗎?(幫助構(gòu)成疑問結(jié)構(gòu))[注]在否定結(jié)構(gòu)中，not須放在助動詞后面。2)助動詞加not一般都有簡略式，用于口語中。如：is notisn39。t would notwouldn39。tare notaren39。t [B:nt] have nothaven39。twas not wasn39。t has nothasn39。twere not weren39。t [wE:nt] had nothadn39。tshall notshan39。t [FB:nt] do notdon39。t [dEunt]will notwon39。t [wEunt] does notdoesn39。tshould notshouldn39。t did notdidn39。t2. be助動詞be的形式變化和動詞be。be作為助動詞的用法有下列幾種：1)be后跟動詞的現(xiàn)在分詞 可以構(gòu)成各種進行時態(tài)。如：The driver is cleaning the 。Yesterday afternoon we were discussing a new 。Women in our country are playing an important part in socialist 。2) be后跟動詞的過去分詞 可以構(gòu)成被動語態(tài)。如：A lot of consumer goods are made of 。The Flower Show is usually held here in October. 花展通常于10月在此舉行。The cinema will be closed for repair from March 。3)be加動詞不定式 有下列各種用法：a)表示未來的安排或計劃。如：The delegation is to leave for Shanghai 。I39。m to be home before 。b)表示必要或命令或問對方的意志。如：You39。re to hand in your exercises 。Where am I to put these tools? 這些工具應(yīng)該放在什么地方?What is to be done?怎么辦?c)表示可能，與can或may相仿。如：I am not sure whether he is to turn up 。My key is nowhere to be 。d) be + about + 動詞不定式則表計劃即將，如：The meeting is about to 。have 的過去式是had。Have (had)作為助動詞和過去分詞一起，構(gòu)成各種完成時態(tài)。如：I have known Mr. Smith for four 。He has not made up his mind 。A woman came in with a baby，who had just swallowed a safety 。[注] have的簡略式是39。ve，has的簡略式是39。s，had的簡略式是39。d，如I39。ve，you39。ve，he39。s，I39。d，we39。d，he39。d，they39。d等。do的過去式是did。do (did)作為助動詞，有下列一些用法：1)構(gòu)成現(xiàn)在一般時和過去一般時的疑問句和否定句。如：Do you know each other? 你們兩人認(rèn)識嗎?How do you find the climate here? 你覺得這里的氣候怎么樣?She did not go to hospital after breakfast She went to work as ，她照常上班去了。2)構(gòu)成否定的祈使句。如：Don39。t be so 。Do not hesitate to e when you need 。3)加強陳述句和祈使句的語氣。如：I do think he is 。Do e 。Do ask，if you have any ，務(wù)必提出。4)用于倒裝句中。如：Only then did I understand the importance of ，我才了解到科學(xué)的重要性。Never did I expect to see him 。5)還可用來代替主要動詞，以避免重復(fù)。較常用在簡略答語中。如：Does he also study geography?他也學(xué)地理嗎? ――Yes，he ，他也學(xué)地理。Did it snow a lot last week? ――Yes，it did。上星期雪下得多嗎? 是的，下得很多。He works even harder than you do. 他比你還要用功。[注] 上面最后一句中的do應(yīng)喚作替代詞，只是為了初學(xué)者的方便而放在助動詞項下。3. shall和Will助動詞shall本身沒有詞義，只用在第一人稱的將來時態(tài)中(現(xiàn)多為will所代替)。在將來一般時中，shall后接動詞原形。如：I shall think it 。Don39。t worry. We shall tell you all about 。我們都會告訴你的。1)助動詞will本身沒有詞義，只用在第二、三人稱的將來時態(tài)中。will在將來一般時中后接動詞原形。如：He will be twentyfive years old next 。You will have an examination in English 。The weather forecast says that