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1、.,Be动词,一般现在时中be动词的用法 be am is are （1）am用在I后 I am a student. Im happy. （2）are用于复数主语和第二人称单数（你，您）等情况 Are you Chinese? They are basketball players. The books are expensive.,.,（3）is用在主语是第三人称单数或不可数名词等情况 He is my friend. The dog is yellow. Time is money. be动词的缩写形式 I am = Im he/she/it is = hes/shes/its we/y
2、ou/they are = were/youre/theyre is not = isnt are not = arent who is = whos what is = whats,.,be动词的在一般现在时中的各种句型 1）肯定句： 主语 + be + 其他成分 She is beautiful. 2）否定句： 主语 + be + not + 其他成分 She is not beautiful. 3）一般疑问句（用yes或no来回答）：be + 主语 +其他成分 + ？ Is she beautiful？ 4）特殊疑问句： 疑问词 + be + 主语（其他成分）+ ？ Whats your
3、 name? Whos that?,.,be的用法口诀： 我用am，你用are, is跟着他、她、它。 单数is，复数are，勿忘be的三变化。 变疑问，往前提，句末问号莫丢弃。 变否定，更容易，be后not莫忘记。 疑问否定任你变，句首大写莫迟疑。 一般现在时中be动词的用法相对简单，上面的口诀基本包括了be动词的各种问题。,.,Exercises,用am/is/are填空 1、She（ ）a student. 2、His jacket （ ）on the table. 3、We （ ）family. 4、-How （ ）you? -I （ ）fine, thanks. 5、Jack and
4、 I （ ）good friends. 6、（ ）she a student? 7、（ ）you a teacher?,.,助动词do/does,什么是助动词？ 顾名思义，助动词就是帮助动词的，而本身没有实际意义的动词，是具有雷锋精神的词汇。 助动词do的三种变化形式 do 第三人称单数时使用的does 过去式did,.,do的基本用法： 1 构成否定句 2 构成一般疑问句及回答 3 构成特殊疑问句 do的各种形式 肯定式：do 否定式：dont/do not do用在第一人称单复数、第二人称单复数和第三人称复数作主语，且时态为一般现在时的句子，如： I like that dress. 否定
5、句：I dont like that dress. 一般疑问句及回答：-Do you like that dress? -Yes, I do/ No, I dont.,.,特殊疑问句：Which dress do you like? does 肯定式：does 否定式：doesnt does用在第三人称单数作主语，且时态为一般现在时的句子 当does出现时，句子中用动词原形。如： She likes that dress. 否定句： She doesnt like that dress. 一般疑问句及回答：-Does she like that dress? -Yes, she does./N
6、o, she doesnt. 特殊疑问句：Which dress does she like?,.,Exercises,按要求改写句子： 1. Ithinkheisveryold.(否定句) I_thinkhe_veryold. 2. Thissignmeans“Nosmoking”.（改为特殊疑问句） What_thissign_? 3. Myplanthastwogreenleaves.(就划线部分提问) _ _ _ _ _ _plant _? 4. I love my parents.（改为一般疑问句） _?,.,翻译句子 1 他不喜欢花。 2 他每天做什么？ 3 How do you
7、go to school? 4 Which film do you like best?,.,情态动词,情态动词有一定的意义 无人称和数的变化 除了ought和have通常不带to，后加动词原形 表示说话人的语气或情绪（请求、警告、命令等）,特点：,.,情态动词,need,will/would,can/could,have/had to,may/might,used to,ought to,dare,shall/should,must,.,1. can/could 1) 表示能力 I can speak English and French. He can do it himself. 2)
8、表示事物一时的特征，理论上的可能性 Its always warm here, however, sometimes it can be very cold. Even an experienced teacher can make mistakes. 3) 表示允诺，许可 -Can I eat some candies, mom? -Yes, you can./No, you cant. You can have my seat. I am going now.,.,4) 表示推测 -Someone is knocking at the door. Who can it be? Can it
9、 be Tony? -No, it cant be him. He is in Beijing now. No, he couldnt be a thief. Could是can的过去式，用法与can类似，常用于过去时中；could 用在现在时中表示表示委婉、客气，相当于can。 -Could you help me?/Could you do me a favor? -Sure./Certainly.,.,2. may和might 1) 表示请求或许可 -May/Might I come in? -Yes, you may. 2) 表示可能性的推测 She has changed so mu
10、ch that you may well not recognize her. Its too late. I think he may/might have gone to bed. 3) may用于祈使句表示祝愿 May you succeed! May you return in safe! 关于may的一般问句的回答：肯定回答为 “Yes,please./Certainly./Sure.” 否定回答为“Please dont./No, you cant/musnt.”,.,might是may的过去式，用法与may类似，常用于过去时中；用在疑问句中，还可表示委婉客气。,.,3. must
11、 1) 必须 Must I say sorry? Yes, you must./No, you neednt./No, you dont have to. You must see a doctor. 2) 猜测，“肯定，准是” She must be doing her homework now. There must be something wrong with my computer. It must have rained last night. The ground is wet.,.,3) 偏要，硬要 If you must smoke, please go out. 4) 否定
12、，表示“禁止” You mustnt play with fire. You may hurt yourself. must一般疑问句的否定回答用neednt或dont have to, 而不用 mustnt. 因为mustnt表示“不可能，禁止”，语气比较强硬,.,提到must,就不得不讲到它和have to的对比。 1) 二者都有“必须”的意思，have to表示客观上的需要，有被迫的意为，表示“不得不.”；must表示说话人主观上的看法，即主观上的必要。 ex: My brother is ill, so I have to call the doctor in the middle o
13、f the night. I must work hard for my future. 2) have to有人称、时态和单复数上的变化，而must只有一种形式。 have to had to I have to/she has to ex: He had to look after his sister, because his parents were not at home yesterday. 3) 在否定形式中，“dont have to”表示“不必”,“musnt”表示“禁止” ex: You dont have to tell him this news. 你不必告诉他这个消息
14、。 You musnt tell him this news. 你一定不要告诉他这个消息。,.,4. shall的用法 1)shall常用于第一人称，表示简单的将来，构成将来时态。(助词) ex: I shall think it over and let you know my idea. When shall we meet again? We shall have a good time in the park. 2) shall用于第一人称，还可以表示征求对方的意愿。 ex: What shall we do this evening? Shall we go to the movie
15、s? 3) shall用于第一、第三人称疑问句中，表示说话人征求对方的意见或向对方请示。 ex: Shall we begin our lesson?（征求意见） When shall he be able to leave the hospital?（请示） 4) shall用于第二、第三人称，表示说话人给对方命令、警告、允诺或威胁。,.,ex: You shall fail if you dont work harder. (警告) He shall have the book when I finish reading. (允诺) You shall get a bike as your birthday. (允诺) He shall be punished. (威胁) shall实际上是一个情态助词，表示“将要、要不要、应该”等意义，语气比较委婉，用于疑问句时意思为“干.好吗？”“要不要.”,.,shall和will的对比 1）shall
