英语情态动词的用法.docx

1、英语情态动词的用法英语情态动词的用法情态动词 1） 情态动词不能表示正在发生或已经发生的事情，只表示期待或估计某事的发生。 2） 情态动词 除ought 和have 外，后面只能接不带to 的不定式。 3） 情态动词没有人称，数的变化，即情态动词第三人称单数不加-s。 4） 情态动词没有非谓语形式，即没有不定式，分词，等形式。 情态动词有can (could), may (might), must, have to, shall (should, will (would), dare (dared), need (needed), ought to等。 情态动词无人称和数的变化；不能单独使用，

2、必须与其后的动词原形构成谓语 一、 can, could 1) 表示能力（体力、知识、技能）。 Can you lift this heavy box?（体力） Mary can speak three languages.（知识） Can you skate?（技能） 此时可用be able to代替。Can只有一般现在时和一般过去式；而be able to则有更多的时态。 Ill not be able to come this afternoon. 当表示“经过努力才得以做成功某事”时应用be able to，不能用Can。如： He was able to go to the part

3、y yesterday evening in spite of the heavy rain. 2) 表示请求和允许。 -Can I go now? - Yes, you can. / No, you cant. 此时可与may互换。在疑问句中还可用could, might代替，不是过去式，只是语气更委婉，不能用于肯定句和答语中。 - Could I come to see you tomorrow? - Yes, you can. ( No, Im afraid not. ) 3) 表示客观可能性（客观原因形成的能力）。 Theyve changed the timetable, so we

4、 can go by bus instead. This hall can hold 500 people at least. 4) 表示推测（惊讶、怀疑、不相信的态度），用于疑问句、否定句和感叹句中。 Can this be true? This cant be done by him. How can this be true? 二、 may, might 1) 表示请求和允许。might比 may语气更委婉，而不是过去式。否定回答时可用cant 或mustnt，表示“不可以，禁止”。 -Might/ May I smoke in this room? - No, you mustnt.

5、- May/Might I take this book out of the room? - Yes, you can. (No, you cant / mustnt. ) 用May I.？征徇对方许可时比较正式和客气，而用Can I.？在口语中更常见。 2）用于祈使句，表示祝愿。 May you succeed! 3) 表示推测、可能性（不用于疑问句）。 might不是过去式，它所表示的可能性比may小。 1He may /might be very busy now. 2Your mother may /might not know the truth. 三、 must, have to

6、 1) 表示必须、必要。 You must come in time. 在回答引出的问句时，如果是否定的，不能用mustnt（禁止，不准），而用neednt, dont have to（不必）. - Must we hand in our exercise books today? - Yes, you must. - No, you dont have to / you neednt. 2) must是说话人的主观看法， 而have to则强调客观需要。Must只有一般现在时， have to 有更多的时态形式。 1 he play isnt interesting, I really mu

7、st go now. 2 I had to work when I was your age. 3) 表示推测、可能性（只用于肯定的陈述句） 1 Youre Toms good friend, so you must know what he likes best. 2 Your mother must be waiting for you now. 四、 dare, need 1) dare作情态动词用时, 常用于疑问句、否定句和条件从句中, 过去式形式为dared。 1 How dare you say Im unfair? 2 He darent speak English before

8、 such a crowd, dare he? 3 If we dared not go there that day， we couldnt get the beautiful flowers. 2) need 作情态动词用时, 常用于疑问句、否定句。在肯定句中一般用must, have to, ought to, should代替。 1You neednt come so early. 2. - Need I finish the work today? - Yes, you must. / No, you neednt. 3) dare和 need作实义动词用时， 有人称、时态和数的变化

9、。在肯定句中，dare后面常接带to的不定式。在疑问句和否定句中，dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。 1. I dare to swim across this river. 2. He doesnt dare (to) answer. 3. He needs to finish his homework today. 五、 shall, should 1) shall 用于第一人称，征求对方的意见。 What shall we do this evening? 2) shall 用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。 1. Y

10、ou shall fail if you dont work hard.(警告) 2. He shall have the book when I finish it.(允诺) 3. He shall be punished.(威胁) 六、 will, would 1) 表示请求、建议等，would更委婉。 Will / Would you pass me the ball, please? 2) 表示意志、愿望和决心。 1. I will never do that again. 2. They asked him if he would go abroad. 3) would表示过去反复发

11、生的动作或某种倾向。would表示过去习惯时比used to正式，且没有“现已无此习惯”的含义。 1. During the vacation, he would visit me every other day. 2. The wound would not heal. 4) 表示估计和猜想。 It would be about ten oclock when she left home. 七、 should, ought to 1) should, ought to表示“应该”，ought to表示义务或责任，比should语气重。 1. I should help her because

12、 she is in trouble. 2. You ought to take care of the baby. 2) 表示劝告、建议和命令。should, ought to可通用，但在疑问句中常用should。 1. You should / ought to go to class right away. 2. Should I open the window? 3) 表示推测 should , ought to (客观推测), must(主观推测)。 1.He must be home by now. (断定他已到家) 2.He ought to/should be home by

13、now.(不太肯定) 3. This is where the oil must be.(直爽) 4. This is where the oil ought to/should be.(含蓄) 09牛津中考英语专项训练及答案(9)(缺词填空)(1)At different times in a mans life his food has different effects (影响) on his body. Among children f (1) is quickly changed to the power(力量) to run and play games. Most of a yo

14、ung mans food is spent on growing t (2); we grow upwards only d (3) the first twenty years of our l (4), not later. Working men get their strong bodies from their food; and if they work h (5), they do not get fat. Office workers eat well and s (6) down a lot, and may begin to grow fat when still qui

15、te young. Many older p（7) try to work much and walk often. Perhaps the most difficult time is when a man r (8) sixty years of age. His body and mind b (9) restful, without much work or interest. That is when food changes quickly to f (10).1._ 2._ 3._ 4._ 5._ 6._ 7._ 8._ 9._ 10._(2)Bats(蝙蝠) are the o

16、nly flying “animals” in the world. It is known to all that they cannot see very well. “As b_(1) as a bat” is often h_(2). Yet, they have no trouble flying on the d_(3) nights and finding their way r_ (4) very well. Why can bats fly and see at night? They fly by “radar(雷达)”. The bats radar w_ (5) the

17、 same way as the radar on ships and planes. As a bat flies t_(6) the air, it makes a sound. If the sounds hit t_(7), they will come back and the bats e_(8) will receive the message. In this way, the bat is a_(9) to know where the things are. Bats go out for f_(10) at night. In the daytime, they hang

18、 in some dark places. 1._ 2._ 3._ 4._ 5._6._ 7._ 8._ 9._ 10._（3）Tennis is in its second life. Its first game began in France. The name of the game comes from the French word “tennez”. The English men c_1_ the game “tennis” when they watched the Frenchmen play 800 years ago. The Englishmen liked the

19、French game. Tennis courts（球场）were built in every park, in every city, just like today. The two countries played against each other. At first they played for honor. Then they w_2_ money. Later people began cheating（欺骗）to get money. Three hundred years ago the game was forbidden（禁止）to stop the cheati

20、ng. The game a_3_ disappeared.Americans found the old courts when they went to Europe 100 years ago. They learned w_4_ they could do about the game. They liked the game as the Englishmen had b_5_. After returning home, the Americans built tennis courts. Tennis began to become w_6_ in all the United

21、States. Now it is one of the most e_ games in the world again.1._2._3._4._5._ 6._ 7._ _(4)There are four people in my family. Every day my parents are very busy t 1 to make money in order to pay the high tuition(学费）for my brother and me. They hardly say I love you or send f 2 to each other. Besides，

22、my father has a bad temper(脾气）It is easy for him to lose his temper w 3 hes very tired from the hard work. I didnt know whether there was love between them u 4 one spring. At that time，my father suddenly got badly sick .My mother had to stay with him in the hospital for a month. When they returned f

23、rom the hospital，they both looked very w 5 as if both of them had a serious illness.After they were back，my mother helped my father walk slowly on the country road every day in the morning and dusk. H 6 ，after two months my father still couldnt walk by h 7_ All of us were worried about him.Dad，how a

24、re you f 8 now? I asked him one day.Susan，dont worry about me.”he said i 9 a low voice.“I just like walking with your mom. I like this kind of life.”Reading his eyes，I know he loves my mother very much. Once I thought love m 10 flowers，presents and sweet kisses. But from this experience，I understand

25、 that love is inside，making life strong and warm.1._ 2._ 3._ 4._ 5._6._ 7._ 8._ 9._ 10._(5)A woman was eating in a restaurant,. She asked the waiter to do many t_1_ for her. Now she was g_2_ the waiter a lot of trouble. f_3_, she asked the waiter to turn on the air conditioner because she f_4_too ho

26、t. Then she asked him to t_5_it off because she was too cold. This went on and on for n_6_ half an hour. But the waiter was very kind and _h_7_. He did everything the woman asked _h_8_ to do without getting angry. F_9_, someone else in the restaurant asked why the w_10_didnt just throw the woman out

27、. “Oh, I dont care.” The waiter said and smiling, “We dont even have an air conditioner.”1._ 2._ 3._ 4._ 5._6._ 7._ 8._ 9._ 10._（6）Ask people to name a safe place and most will say “Home”. But every year the British Governments survey（调查）shows that home can be a d_1_ place. Last year 7 British citiz

28、ens(公民) died while putting up their Christmas decorations（装饰）. Over 1,600 needed m_2_ help after falling off their chairs. And 70 people had fatal (致死的) accidents while lying in bed. It is safe to say that n_3_ activity（活动）is without danger.Some of these accidents are just the risks (冒险)of modern li

29、ving. We prefer to risk having a washing machine that might hurt us rather than be safe spending hours cleaning our clothes by h_4_. But most fatal accidents are not the result of mechanical(机械的)failure. The two most common are falling down the stairs and going to s_5_ in the bath. This s_6_ that we are in a more dangerous situation when we feel s_7_.1._ 2._ 3._ 4._ 5._ 6._ 7._ (7)International organizations are f_1_ to help the childrenThese p