现在完成时
? 1、表示截止现在业已完成的动作
eg By now, I have collected all the data that I need.
? 2.表示发生在过去而对现在产生影响、带来结果的动作 eg She has been to the United States.
? 3.表示过去发生的动作持续到现在，并可能还要延续 eg I have learned English for 8 years.
[基本结构]现在完成时的基本结构
? 由 have 加动词的过去分词构成，主语是第三人称单数时，要将 have 改为 has。 例句： I have seen the film already. 我已经看过那部电影了。(现在我知道电影的内容了。) Have you seen my bag? 你看到我的手提包了吗? (你知道它在哪里? ) She has been a dancer for ten years. 她已当了十年的舞蹈演员了。 We’ve planted thousands of trees in the past few years. 过去几年我们种了成千上万棵树。
[时态详解]现在完成时最详细解析
? 对于初接触现在完成时的人来说，往往会产生一种茫然，因为它似乎与一般过去时
相似。那就是，这两种时态描述的动作都始于过去。其实不然，现在完成时主要表示，发生在过去的动作延续到现在刚刚完成、或许还要延续；侧重于这个动作对现在带来的结果、产生的影响、积累的总和等等。而一般过去时则只不过是表示动作发生在过去的什么时候。弄清了这一区别，就很容易理解现在完成时了。它主要适用于下面的几种情况： 1）表示截止现在业已完成的动作 By now, I have collected all the data that I need .到现在为止，我已收集到了我所需的全部资料。 She has read 150 pages today .她今天已看了150页。 We haven't met for many years .我们已多年没见了。 They have developed a new product .他们研制成功了一种新产品。 2）表示发生在过去而对现在产生影响、带来结果的动作 Have you had your dinner? 你吃晚饭了吗？ She has been to the United States. 她已去美国了。 You have grown much taller.你长高了许多。 3）表示过去发生的动作持续到现在，并可能还要延续 It has been five years since he joined the army .他参军五年了。 They have learned English for eight years .他们已学了八年的英语了。 So far we've only discussed the first five chapters.至今我们还只讨论了前五章。 ? 几点注意
1)一个句子应该用什么时态只能取决于它需要表达的意思，以及它所处的语言环境。例如： He speaks English .（一般现在时，说明动作发生的经常性。） He spoke English when he was in New Zealand .（一般过去时，说明动作发生的时间。） He is speaking English.（现在进行时，说明动作正在进行。） He has spoken English for three years since he came to the USA.（现在完成时，这里说明动作的总和。） He has been speaking English since he came to the USA. （现在完成进行时，强调动作的连续性。）
2）在含有时间状语从句或条件状语从句的主从复合句中，如果主句的谓语动词是一般将来时，那么从句的谓语动词就只能用一般现在时来表示将来时；如果主句的谓语动词是过去将来时，那么从句的谓语动词就只能用一般过去时来表示过去将来时。 例如：I will not play tennis if it rains tomorrow. I would not play tennis if it rained the next day. 3) 有些动词表示无法持续的动作，它们一般不宜用于进行时态中。这类动词常见的有：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动词若是用于进行时态，可表示暂时、短暂的情况或表现。例如： Tom is being a good boy today .汤姆今天很乖。 He is being childish .他这样做是耍孩子气。 You are not being modest .你这样说不太谦虚。 4）关于现在完成时的时间状语问题 A. 凡是\完成时态\都表示，不知道也不管动作发生的具体时间, 所以在使用现在完成时的句子里，不可以带有表示具体过去时间的状语，如：yesterday , last week ( month , year , etc. ) , two weeks ago , in 1999等；但常和有些副词连用，如： just , before , already , often , never , ever , not…yet , always等等。 B. 在以when提问的特殊疑问中不能用现在完成时。另外，ago不能用于现在完成时的句子里，因为它表示从现在算起的以前某个时间，属于表示具体过去时间的状语。但是可以用before 来表示\以前\的意义，因为它只表示\以前\，而不知什么时候的以前。 C. 如果是不表示连续性的动词用于现在完成时的句子，不可以和以for表示的\一段时间\的状语连用。在这种情况下，应该用\；since…\的句式来表达。如： He has joined the army for five years. （错误） It has been five years since he joined the army.（正确）
[特殊用法]让现在完成时一目了然的词语
? 能与现在完成时连用词语很多，如副词just, already, yet, before, ever, recently 等，
但下面是一些典型而且重要的例子： (1) since(自从)：不管用作介词、连词还是副词, 句子(主句)谓语通常都用现在完成时： I haven’t seen her since last week. 自上周以来我一直未见过她。 Where have you been since I last saw? 自我上次见到你之后你到哪里去了?
【注】有时可用其他时态的情况，但须注意： ① 对于某些表示状态的动词(如 seem 等)，或因语义等方面的原因，有时可能用一般现在时比较现在完成时更合适： It seems like years since we last met. 我们似乎几年未见面了。 Since when does the $42 plus $5 service charge come to $48? 从什么什候开始42元加5元的服务费等于48元了? ② 若不是指从过去持续到现在，而是指从较远的过去持续到在一个较近的过去，则用过去完成时： Yesterday he told me that he hadn’t eaten anything since Tuesday. 他昨天告诉我自星期二以来他一直未吃任何东西。(指从星期二至昨天未吃东西) ③ 表示时间长度时，通常用一般现在时代替现在完成时： It’s ten years since he left here. 他离开这儿已10年了。 (2) so far(到目前为止)： So far there has been no bad news. 到现在为止还没有什么坏消息。 We haven’t had any trouble so far. 到目前为止，我们还没有遇到任何麻烦。
(3) in [for, during] the past [last] … years(在过去…年中)： In the past two years I’ve seen him little. 过去两年我很少见到他。 I have been here (for) the last [past] month. 最近一个月里我都在这儿。 【注】在一定的上下文里，若是以过去时间为起点，也可用过去完成时。 (4) up to [until] now(到现在为止)： Up to now, the work has been easy. 到现在为止这工作还算容易。 I have heard nothing from him up to now. 到现在为止我还没有听到他一点音信。 (5) It’s [will be] the first time that…(第一次…)： It’s the first time I’ve come here. 这是我第一次来这儿。 Don’t forget, it’ll be the first time I’ve spoken in public. 别忘了，这是我第一次在公共场合发言。
过去将来时
? 1.宾语从句或间接引语中
eg He didn't expect that we would all be there. ? 2.表示过去习惯性的动作
eg During that period, he would do this every day. ? 3.表示过去的愿望、倾向，多用于否定句
eg They knew that we would never permit such a thing.
[基本结构]过去将来时的基本结构
? 过去将来时由would, was/were going to, was/were to was/were about to等加动词原形
构成, 也可由was/were on the point of加动名词构成。 例句：
I knew you would agree. 我知道你会同意的。
I said I would arrange everything. 我说我来安排一切。
[时态详解]过去将来时最详细解析
? 表示过去的某时以后将要发生的动作。但这个\将来\时间绝不会延伸到“现在”；而
仅限于“过去时间区域内”。由此可以看出，含这个时态的句子常带一个表示“过去某个时间点”的状语。这个状语或是一个短语，或是一个句子。这个时态常用于： A）宾语从句或间接引语中；B）表示过去习惯性的动作；C）表示过去情况中的“愿望”、“倾向”，多用于否定句。例如： A) When I thought about it , I wondered what their reaction would be . 当我考虑这件事时，我想知道他们的反应是什么。 She told me that she would go on trip to Europe the next day. 她告诉我，她第二天要去欧洲旅行。 He didn't expect that we would all be there. 他没料到我们会全在那儿。 B) During that period , he would do morning-exercises every day. 在那段时间，他每天早锻炼。 Whenever he had time, he would help his mother with some housework. 无论他什么时间有空,他总是帮他妈妈干点家务活。 C) No matter how difficult the work was , he would keep on doing it until he accomplished it . 不管工作有多难，他总会坚持不懈地把它干完。 They knew that we would never permit such a thing. 他们知道我们绝不会允许发生这样的事。
Even after the lecture ended, the audience would not leave . 甚至在讲座结束之后，听众仍不肯离去。
[特殊用法]几种结构表未曾实现的意图
? was / were going to + 动词原形；was / were to + 动词原形；was / were about to + 动
词原形等结构都可表达当时一种未曾实现的意图或打算。如： The conference was going to be held the next month. 会议下个月开。 We were to have our class at eight. 八点我们该上课了。 I was about to tell him about it when Wu Dong got in. 就在我要告诉他时，吴东进来了。
练习一
1. Sales of CDs have greatly increased since the early 1990s, when people ________ to enjoy the advantages of this new technology.
A. begin B. began C. have begun D. had begun 2. Turn on the television or open a magazine and you ________ advertisements showing happy families.
A. will often see B. often see
C. are often seeing D. have often seen
3. —I hear Jane has gone to the Holy Island for her holiday. —Oh, how nice! Do you know when she ________? A. was leaving B. had left C. has left D. left 4. —What were you doing when Tony phoned you?
—I had just finished my work and________ to take a shower. A. had started B. started C. have started D. was starting 5. I ________ you not to move my dictionary—now I can’t find it. A. asked B. ask C. was asking D. had asked 6. —Has Sam finished his homework today? —I have no idea. He ________ it this morning.
A. did B. has done C. was doing D. had done 7. —What’s that terrible noise?
—The neighbors ________ for a party.
A. have prepared B. are preparing C. prepare D. will prepare
8. Now that she is out of a job, Lucy ________ going back to school, but she hasn’t decided yet.
A. had considered B. has been considering C. considered D. is going to consider
9. The teacher, with 6 girls and 8 boys of her class, ________ visiting a museum when the earthquake struck.
A. was B. were C. had been D. would be
10. The discussion ________ alive when an interesting topic was brought in. A. was coming B. had come C. has come D. came
11. Because the shop ________ , all the T-shirts are sold at half price. A. has closed down B. closed down C. is closing down D. had closed down
12. Let’s keep to the point or we ________ any decisions. A. will never reach B. have never reached C. never reach D. never reached
13. My mind wasn’t on what he was saying so I’m afraid I ________ half of it. A. was missing B. had missed C. will miss D. missed
14. It is said in the book that Thomas Edison (1847—1931) ________ the world-leading inventor for sixty years.
A. would be B. has been C. had been D. was 15. —You were out when I dropped in at your house.
—Oh, I ________ for a friend from England at the airport.
A. was waiting B. had waited C. am waiting D. has waited
练习二
1. She has set a new record, that is, the sales of her latest book ________ 50 million. A. have reached B. has reached C. are reaching D. had reached 2. He kept looking at her, wondering whether he ________ her somewhere. A. saw B. has seen C. sees D. had seen