一、动词时态
(一)动词的基本时态
  英语时态用共有十六种时态,其中常用的有8种,它们是:一般现在时、一般过去时、一般将来时、现在进行时、现在完成时、过去进行时、过去完成时和过去将来时。
1.一般现在时:
(1)表示经常发生、习惯性动作。
  I go to work on foot. 我走着去上班。
(2)客观真理,客观存在,科学事实。
  The sun rises every morning. 太阳每天早上都升起。
【注意】此用法如果出现在宾语从句中,即使主句是过去时,从句谓语也要用一般现在时。
    例:Columbus proved that the earth is round. 哥伦布证明了地球是圆的。
(3)表示格言或警句中。
  It is easy to say than to do. 说比做容易。
(4)现在时刻的状态、能力、性格、个性。
  I want to have a drink. 我想喝水。
(5)某些动词如come, go, move, stop, leave, arrive, be, finish, continue, start等,在一般现在时句中可用来表示将来肯定会发生的动作。
  The bus leaves the station every five minutes. 公交车每隔五分钟离站一次。
(6)在时间状语从句或条件状语从句中,一般现在时代替一般将来时。
  I will tell you if you go with me. 如果你和我走我就告诉你。
  I'll go there after I finish my work. 我干完活儿就去那儿。

2.一般过去时的用法
  表示过去某一时刻或某一段时间内所发生的动作或情况,通常一般过去式带有表示动作时间状语的词,词组或从句,如yesterday, the day before yesterday, last month, three weeks ago等,上下文清楚时可以不带时间状语。
  I was a teacher two years ago. 两年前我是一名老师。
【注意】
(1)过去经常反复发生的动作,也可用used to或would加动词原形来表达,例如:
  I used to do exercise every morning. 我每早都习惯晨练。
(2)"used to"也可用于表示过去曾经存在过的状态。例如:
  That old woman used to be beautiful. 这个老太太曾经很漂亮。

3.一般将来时的用法
(1)表示将来的动作或状态。例如:
  I shall attend the meeting tomorrow. 明天我将参加这个会。
(2)表示将来反复发生的动作或存在的状态。例如:
  She will go to see doctor every week. 她将每周都去看医生。
(3)表示将来的意愿,决心,许诺, 命令等时常用will,征求对方意见,主语是第一人称时,常用shall。
  Shall I sit down? 我能坐下么?
(4)be + going + 动词不定式。也是一种将来时句型,表示打算,计划,最近或将来要作的某事。
  Jack is going to be on business next month. 杰克下个月出差。
(5)be + 动词不定式。表示有职责,义务,可能,约定,意图等。
  We are to see you off. 我们会给你送行。
(6)be about + 动词不定式,表示马上,很快作某事。
  They are about to leave. 他们马上离开。

4.现在进行时的用法
(1)现在进行时的用法表示说话者说话时正在发生或者进行的动作,它注重现在正在进行的动作,而不管动作从什么时间开始,到什么时间结束。
  What are you doing now? 你正在做什么?
  I am looking for my picture. 我在找照片。
(2) 现在进行时表示目前一段时间内正在进行的动作(但说话时这个动作不一定在进行)。
  The students are preparing for the examination. 学生们在准备考试。
(3) 某些动词的现在进行时可以表示即将发生的动作,这些动词有 arrive, come, leave, start等。
  The bus is coming soon. 公交车马上就来了。
(4)替一般现在时,描绘更加生动。
   The Changjiang River is flowing into the east. 江水滚滚向东流。
   The sun is rising in the east. 太阳从东方冉冉升起。
(5)表示按计划安排即将发生的动作。例如:
   She is leaving for Beijing. 她要去北京。
   He is working as a teacher tomorrow. 从明天起他要做老师。
   My father is coming to see me this Saturday. 这个星期六我爸爸要来看我。
【注意】有些动词一般不可以用于进行时态
①表示状态的动词,尤其是静态动词,如:be, have
②表示认识、知觉和情感的动词,如:know, think, hear, find, see, like, want, wish, prefer等。

5.现在完成时的用法
(1) 现在完成时表示在说话之前已经完成或刚完成的动作。
  I have finished my work. 我已经完成了工作。
(2)现在完成时表示动作从过去开始持续到现在,或者还有可能持续下去的动作或状态。 现在完成时常与for 和 since 引导的短语或从句连用。
  I have been a driver for 10 years. 我当司机已经10年了。
  They have worked here since they left college. 他们毕业后就在这里工作。
(3)表示“曾经到过某地(人已回来)”,用"have/has been to";表示“到某地去了(还未回来)”,用"have/has gone to"。
  -- Where is Li Hua?                      -- She knows a lot about Shanghai.
  -- He has gone to the reading-room.              -- She has been there.
(4)短暂动词(即瞬间动词),join, lose, buy, borrow, leave, go, come, arrive, die, marry, finish, complete, begin, start, break out等,在完成时态中,其肯定式不能和表示一段时间的状语连用。
  不能说:He has finished the work for three hours. 要翻译“他已完成工作三小时了。”
   可采用1)“ago法”:He finished the work three hours ago.
      2)“延续法”:He has been through (with) the work for three hours.
      3)“since法”:It is/has been three hours since he finished the work.
【注意】一般过去时与现在完成时的区别
  过去时表示过去某时发生的动作或单纯叙述过去的事情,强调动作;现在完成时为过去发生的,强调过去的事情对现在的影响,强调的是影响;一般过去时常与具体的时间状语连用。
  试比较:
  I saw this film yesterday.(强调看的动作发生过了,不涉及现在)
  I have seen this film.(强调对现在的影响,电影的内容已经知道了)

6.过去进行时的用法
(1)表示过去某一时刻或某一段时间内正在进行的动作(这一过去时间须用时间状语表示)。
   He was preparing his lecture all day yesterday. 他昨天一天都在准备他的讲稿。
(2)表示过去某时正在进行的状态或动作。
  I was watching TV when she came to see me. 她进来的时候我正在看电视。
【注意】过去进行时和一般过去时都是过去发生的事情,但过去进行时侧重表示过去某一时刻正在进行的动作或所处的状态,强调动作的连续进行,而一般过去时则表示单纯的过去事实,例如:
  They were researching a new hot topic last month. (上个月正在研究,研究好与否不知)
  They researched a new hot topic last month. (上个月研究好了,动作已经完成)

7.过去完成时的用法
(1)表示在过去某一时间以前已经完成的动作。例如:
  He had shut the door before the dog came up.
  Everything had been all right up till this morning.
(2)表示动作或状态从过去某个时刻开始一直延续到另一个过去时刻才完成,甚至还要继续下去。
  At the age of ten, he had learned 500 English words.
  He had been ill for a week when we learned about it.
(3)常用hope, expect, think, intend, want, suppose等动词的过去完成时来表示未实现的希望、打算或意图。例如:
  We had expected that you would be able to win the match.
  过去完成时表示过去某一时刻或某一动作之前完成的动作或所处的状态,过去完成时常和 by, before 等词组成的短语和从句连用。
  I had waited for two hours before Tom came.在汤姆来之前我已经等了两个小时。

8.过去将来时的用法
  过去将来时表示从过去某个时间看将要发生的动作或存在地状态,过去将来时较多地被运用在宾语从句中。
  My mother promised to me that she would give me a gift if I passed the exam.
  我妈妈答应我如果通过考试她将送我一个礼物。

(二)动词时态的一些典型用法
1.在if, unless, even if引导的条件状语从句中,在when, before, until (till), as soon as, the moment, once引导的时间状语从句中,no matter what, who, which, when, where, how或 what ever, whoever, whichever, whenever, wherever, however引导的让步状语从句中,如果主句是将来时(往往出现will/shall/can/must)或主句是祈使句,从句一般现在时表示一般将来时。如:
  I'll not go unless I'm invited.
  Tell him the news as soon as he comes.
2."used to/would+动词原形"可以表示过去经常或习惯性的动作。如:
  Often at night she would hear a long low whistle and the sound of a metallic noise.
3."be+to do"表示拟定或计划中将发生的行为或按职责义务必须去做的事情;"be about to do"表示即将发生的事,句中一般不使用时间状语。如:
  All the questions are to be answered at once.
  No one is to leave the room without permission.
辨析
  他们即将动身。
  【误】They are about to leave this afternoon.
  【正】They are about to leave.
4.现在(过去)完成时不能与表示过去特定时间的状语连用;瞬间动词的肯定式现在(过去)完成时不能与段时间状语连用。如:
  【误】He has come to Beijing since last year.
  【正】He has lived in Beijing since last year.
  【误】He has joined the army for 3 years.
  【正】He has served in the army tor 3 years.
  【正】He joined the army 3 years ago.
  【正】He has been a soldier for 3 years.
  【正】It is 3 years since he joined the army.
  【正】He has joined the army.
  常见的瞬间动同有:marry, close, die, arrive, fall, leave, go, break, lose, give, join, jump, receive, buy, borrow, start, begin, graduate等。
5.语境中的过去时,往往表示“刚才,刚刚”之意,暗示现在已“不再这样”。如:
  I didn't know you were here. 我不知道你在这里。
  I never thought he would do that. 我从没想到他会做出这样的事。
6.表示愿望、打算一类的词,如:hope, expect, mean, in tend, want, think, suppose, want等,其过去完成时表示过去未曾实现的愿望或意图。例如:
  I had hoped to see more of ShangHai. 我本希望在上海多看看。(但未能如愿)
  I had meant to help you, but I was too busy at the moment. 我本想去帮你的,但当时确实太忙了。
  I had thought you would come tomorrow. 我原以为你明天才来呢。
7.某些固定句式中的动词时态是固定的、约定俗成的。
(1) This/It is the first/second ... time+that从句。that从句一般用现在完成时,如果把前边的is改为was,则that从句用过去完成时。如:
  This is the first time I have come here.
  It was the third time(that)he had made the same mistake.
(2)It is/has been+一段时间+since从句。since从句中一般用过去时,如果将前边的is改为was,则since从句中用过去完成时。如:
  It was ten years since we had had such a wonderful time.
(3)be about to do...when...意为“即将……(这时)突然……”如:
  I was about to go out when the telephone rang.
(4)be(was/were)+ doing...when...意为“正在于……(这时)突然……”。如:
  They were reading when Tom shouted in pain.
(5)Hardly had... done... when...; No sooner had ... done ... than
  when和than从句里用一般过去时,表示“刚刚……就……”如:
  Hardly(No sooner) had I got home when(than)the rain poured down. 我刚到家大雨就倾盆而下。
(6)It+be+ 一段时间+ before从句
  这个句式分两种情况:如果主句用将来时,则从句用一般现在时表将来时,意为多长时间以后即将发生某事;如果主句用过去时,从句也用过去时,意为多长时间后发生了某事。如:
  It won't be long before he succeeds.(=He will succeed soon.)
  It was ten years before they met again.(=They met again ten years later.)

二、动词的语态

  语态有两种:主动语态和被动语态。
  主语是动作的发出者为主动语态;主语是动作的接受者为被动语态。
1.被动语态的句型
(1)常见句式是:主语(受动者)+be+过去分词+(by+施动者)
例如:He was scolded by the English teacher.
(2)主语+get+过去分词+其它成分
例如:The boy got drowned last summer./ She got fired because of her faults.
注意:使用这种结构不能带有“by+施动者”
(3)带有双宾语(直接宾语和间接宾语)的主动句变为动句,其主语可以是直接宾语,也可以是间接宾语。

例如:She lent me a bike. 变被动 I was lent a bike(by her).
  A bike was lent to me(by her).

(4)情态动词+be+过去分词
例如:This problem must be worked out in half an hour.
(5)双重被动式:主语+被动式谓语+不定式的被动式+其它成分
例如:These magazines are not allowed to be taken out of the reading-room./The murderer was ordered to be shot.

2.主动表被动的几种情况
(1)不及物动词与状语连用,用以表示主语的品质和状态。常见动词是:cut, sell, read, write, fill, cook, lock, wash, drive, keep等。
例如:This knife cuts well. 这把刀好切。 These books sell well. 这些书好卖。
   The cloth washes well. 这种布好洗。 The pen writes smoothly. 这支笔写起来流畅。
   Meat won't keep long in such hot weather. 肉在这样热的天气里放不长久。
(2)一些连系动词的主动式+形容词。常见动look, smell, taste, sound, feel, prove, turn out等。
例如:The apples taste good. The flower smells wonderful.
   The news proved / turned out true. 注:prove也可用于被动式,如:His answer (was) proved right.
(3)不定式在某些形容词之后,且与主语有动宾关系。常见形容词有:hard, defficult, easy, heavy, fit, good, comfortable, convenient, impossible等。
例如:The problem is easy to do. The question is difficult to answer.
   The project is impossible to complete in a year. The box is heavy to carry.
比较:The problem is to be done. / The question is to be answered.没有形容词时,虽然不定式与主语是动宾关系,但必须用被动式。

3.容易误用被动语态的几种情况
(1)I teach myself French. 不可变为Myself is taught French. 因为反身代词不可作主语。
(2)We help each other/one another. 不可变为Each other/One another is helped by us. 因为相互代词不可作主语。
(3)He lost heart. 不可变为Heart was lost by him. 因为象lose heart, make a face, keep silence, lose in thought这类动宾结构的固定短语只能用于主动式,不能用被动式。
(4)She took part in the sports meet. 不能变为The sports meet was taken part in by her. 因为象take part in, belong to,own, have, hate, fail, contain等表状态动词没有被动语态。