【正文】 idn’，但你沒(méi)有來(lái)?！瞵F(xiàn)在完成時(shí)由 have 加動(dòng)詞的過(guò)去分詞構(gòu)成，主語(yǔ)是第三人稱單數(shù)時(shí)，要將 have 改為 has。例句：I have seen the film 。(現(xiàn)在我知道電影的內(nèi)容了。)Have you seen my bag? 你看到我的手提包了嗎?(你知道它在哪里?)She has been a dancer for ten 。We’ve planted thousands of trees in the past few 。對(duì)于初接觸現(xiàn)在完成時(shí)的人來(lái)說(shuō)，往往會(huì)產(chǎn)生一種茫然，因?yàn)樗坪跖c一般過(guò)去時(shí)相似。那就是，這兩種時(shí)態(tài)描述的動(dòng)作都始于過(guò)去。其實(shí)不然，現(xiàn)在完成時(shí)主要表示，發(fā)生在過(guò)去的動(dòng)作延續(xù)到現(xiàn)在剛剛完成、或許還要延續(xù)；側(cè)重于這個(gè)動(dòng)作對(duì)現(xiàn)在帶來(lái)的結(jié)果、產(chǎn)生的影響、積累的總和等等。而一般過(guò)去時(shí)則只不過(guò)是表示動(dòng)作發(fā)生在過(guò)去的什么時(shí)候。弄清了這一區(qū)別，就很容易理解現(xiàn)在完成時(shí)了。它主要適用于下面的幾種情況：1）表示截止現(xiàn)在業(yè)已完成的動(dòng)作By now, I have collected all the data that I ，我已收集到了我所需的全部資料。She has read 150 pages 。We haven39。t met for many 。They have developed a new 。2）表示發(fā)生在過(guò)去而對(duì)現(xiàn)在產(chǎn)生影響、帶來(lái)結(jié)果的動(dòng)作Have you had your dinner? 你吃晚飯了嗎？She has been to the United 。You have grown much 。3）表示過(guò)去發(fā)生的動(dòng)作持續(xù)到現(xiàn)在，并可能還要延續(xù)It has been five years since he joined the 。They have learned English for eight 。So far we39。ve only discussed the first five 。幾點(diǎn)注意1)一個(gè)句子應(yīng)該用什么時(shí)態(tài)只能取決于它需要表達(dá)的意思，以及它所處的語(yǔ)言環(huán)境。例如：He speaks English.（一般現(xiàn)在時(shí)，說(shuō)明動(dòng)作發(fā)生的經(jīng)常性。）He spoke English when he was in New Zealand.（一般過(guò)去時(shí)，說(shuō)明動(dòng)作發(fā)生的時(shí)間。）He is speaking English.（現(xiàn)在進(jìn)行時(shí)，說(shuō)明動(dòng)作正在進(jìn)行。）He has spoken English for three years since he came to the USA.（現(xiàn)在完成時(shí)，這里說(shuō)明動(dòng)作的總和。）He has been speaking English since he came to the USA.（現(xiàn)在完成進(jìn)行時(shí)，強(qiáng)調(diào)動(dòng)作的連續(xù)性。）2）在含有時(shí)間狀語(yǔ)從句或條件狀語(yǔ)從句的主從復(fù)合句中，如果主句的謂語(yǔ)動(dòng)詞是一般將來(lái)時(shí)，那么從句的謂語(yǔ)動(dòng)詞就只能用一般現(xiàn)在時(shí)來(lái)表示將來(lái)時(shí)；如果主句的謂語(yǔ)動(dòng)詞是過(guò)去將來(lái)時(shí)，那么從句的謂語(yǔ)動(dòng)詞就只能用一般過(guò)去時(shí)來(lái)表示過(guò)去將來(lái)時(shí)。例如：I will not play tennis if it rains would not play tennis if it rained the next )有些動(dòng)詞表示無(wú)法持續(xù)的動(dòng)作，它們一般不宜用于進(jìn)行時(shí)態(tài)中。這類動(dòng)詞常見(jiàn)的有：be , believe , consist , find , forget , hate , have , hope , hear , know , like , love , notice , prefer , remember , see , seem , smell , suggest , taste , understand , want , wish , sit down , stand up 等等。Be動(dòng)詞若是用于進(jìn)行時(shí)態(tài)，可表示暫時(shí)、短暫的情況或表現(xiàn)。例如：Tom is being a good boy 。He is being 。You are not being 。4）關(guān)于現(xiàn)在完成時(shí)的時(shí)間狀語(yǔ)問(wèn)題“完成時(shí)態(tài)”都表示，不知道也不管動(dòng)作發(fā)生的具體時(shí)間, 所以在使用現(xiàn)在完成時(shí)的句子里，不可以帶有表示具體過(guò)去時(shí)間的狀語(yǔ)，如：yesterday , last week(month , year , etc.), two weeks ago , in 1999等；但常和有些副詞連用，如： just , before , already , often , never , ever , not?yet , always等等。另外，ago不能用于現(xiàn)在完成時(shí)的句子里，因?yàn)樗硎緩默F(xiàn)在算起的以前某個(gè)時(shí)間，屬于表示具體過(guò)去時(shí)間的狀語(yǔ)。但是可以用before 來(lái)表示“以前”的意義，因?yàn)樗槐硎尽耙郧啊?，而不知什么時(shí)候的以前。，不可以和以for表示的“一段時(shí)間”的狀語(yǔ)連用。在這種情況下，應(yīng)該用“It has been ? ；since?”的句式來(lái)表達(dá)。如：He has joined the army for five years.（錯(cuò)誤）It has been five years since he joined the army.（正確）能與現(xiàn)在完成時(shí)連用詞語(yǔ)很多，如副詞just, already, yet, before, ever, recently 等，但下面是一些典型而且重要的例子：(1)since(自從)：不管用作介詞、連詞還是副詞, 句子(主句)謂語(yǔ)通常都用現(xiàn)在完成時(shí)：I haven’t seen her since last 。Where have you been since I last saw? 自我上次見(jiàn)到你之后你到哪里去了?【注】有時(shí)可用其他時(shí)態(tài)的情況，但須注意：① 對(duì)于某些表示狀態(tài)的動(dòng)詞(如 seem 等)，或因語(yǔ)義等方面的原因，有時(shí)可能用一般現(xiàn)在時(shí)比較現(xiàn)在完成時(shí)更合適：It seems like years since we last 。Since when does the $42 plus $5 service charge e to $48? 從什么什候開(kāi)始42元加5元的服務(wù)費(fèi)等于48元了?② 若不是指從過(guò)去持續(xù)到現(xiàn)在，而是指從較遠(yuǎn)的過(guò)去持續(xù)到在一個(gè)較近的過(guò)去，則用過(guò)去完成時(shí)：Yesterday he told me that he hadn’t eaten anything since 。(指從星期二至昨天未吃東西)③ 表示時(shí)間長(zhǎng)度時(shí)，通常用一般現(xiàn)在時(shí)代替現(xiàn)在完成時(shí)：It’s ten years since he left 。(2)so far(到目前為止)：So far there has been no bad 。We haven’t had any trouble so ，我們還沒(méi)有遇到任何麻煩。(3)in [for, during] the past [last] ? years(在過(guò)去?年中)：In the past two years I’ve seen him 。I have been here(for)the last [past] ?！咀ⅰ吭谝欢ǖ纳舷挛睦铮羰且赃^(guò)去時(shí)間為起點(diǎn)，也可用過(guò)去完成時(shí)。(4)up to [until] now(到現(xiàn)在為止)：Up to now, the work has been 。I have heard nothing from him up to 。(5)It’s [will be] the first time that?(第一次?)：It’s the first time I’ve e 。Don’t forget, it’ll be the first time I’ve spoken in ，這是我第一次在公共場(chǎng)合發(fā)言?！?過(guò)去將來(lái)時(shí)由would, was/were going to, was/were to was/were about to等加動(dòng)詞原形構(gòu)成, 也可由was/were on the point of加動(dòng)名詞構(gòu)成。例句：I knew you would 。I said I would arrange 。表示過(guò)去的某時(shí)以后將要發(fā)生的動(dòng)作。但這個(gè)“將來(lái)”時(shí)間絕不會(huì)延伸到“現(xiàn)在”；而僅限于“過(guò)去時(shí)間區(qū)域內(nèi)”。由此可以看出，含這個(gè)時(shí)態(tài)的句子常帶一個(gè)表示“過(guò)去某個(gè)時(shí)間點(diǎn)”的狀語(yǔ)。這個(gè)狀語(yǔ)或是一個(gè)短語(yǔ)，或是一個(gè)句子。這個(gè)時(shí)態(tài)常用于：A）賓語(yǔ)從句或間接引語(yǔ)中；B）表示過(guò)去習(xí)慣性的動(dòng)作；C）表示過(guò)去情況中的“愿望”、“傾向”，多用于否定句。例如：A)When I thought about it , I wondered what their reaction would ，我想知道他們的反應(yīng)是什么。She told me that she would go on trip to Europe the next ，她第二天要去歐洲旅行。He didn39。t expect that we would all be 。B)During that period , he would do morningexercises every ，他每天早鍛煉。Whenever he had time, he would help his mother with some ,他總是幫他媽媽干點(diǎn)家務(wù)活。C)No matter how difficult the work was , he would keep on doing it until he acplished ，他總會(huì)堅(jiān)持不懈地把它干完。They knew that we would never permit such a 。Even after the lecture ended, the audience would not ，聽(tīng)眾仍不肯離去。was / were going to + 動(dòng)詞原形；was / were to + 動(dòng)詞原形；was / were about to + 動(dòng)詞原形等結(jié)構(gòu)都可表達(dá)當(dāng)時(shí)一種未曾實(shí)現(xiàn)的意圖或打算。如：The conference was going to be held the next 。We were to have our class at 。I was about to tell him about it when Wu Dong got ，吳東進(jìn)來(lái)了