1、1情态动词 can . should情态动词有 can (could), may (might), must, have to, shall (should, will (would), dare (dared),need (needed), ought to 等。今天我们来学 can 和 should.Can1. 特点： 情态动词无人称和数的变化 ；不能单独使用，必须与其后的 动词原形 构成谓语。I can speak English. We can swim. He can sing.You can play the guitar. She can draw. They can dance
2、.22.概念：1）表示能力（体力、知识、技能） 。 e.g. Can you lift this heavy box? 你能举起这个大盒子吗？（体力） Mary can speak three languages. 玛丽能说三种语言。 （知识） Can you skate? 你能滑冰吗？（技能） 2）表示请求和允许。 -Can I go now? - Yes, you can. / No, you cant. 3）表示客观可能性（客观原因形成的能力） 。 e.g. Theyve changed the timetable, so we can go by bus instead. This h
3、all can hold 500 people at least. 这个大厅至少能容纳 500 人。 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。e.g. Can this be true? This cant be done by him. How can this be true? 3.变否定句直接在 can 后加“not”I can not speak English. We can not swim. He can not sing. You can not play the guitar. She can not draw. They can not d
4、ance.4.变一般疑问句直接把 can 提前, 肯定回答用 yes, 否定回答用 no.注意 can 提前后首字母大写例 Can you speak English? Yes, I can. /No, I cant.Can you play the guitar? Yes, we can. / No, we cant.Can she draw? Yes, she can. /No, she cant.Can he sing? Yes, he can./ No, he cant.Can they dance? Yes, they can./ No, they cant.3总结：情态动词 can
5、，后面总是接动词原形 ,没有人称和数的变化 .意思是”能,会”.用法口诀：情动 can 表能力, 和行为动词不分离.不管主语如何变, can 的模样永不变.只要出现情动 can, 动词原形后面站.一般疑问 can 提前, 否定 can 后 not 添.Should1.should 表示义务或责任建议或劝告。其意为 “应该”He should work harder. 他应该更加努力。You should help your mother with the housework. 你应该帮你母亲做家务。Should I wear a coat? 我要穿大衣吗？2.should 表示推断。意为“应该
6、” 、 “可能” He should arrive soon 他可能很快就到了。The train should have already left. 火车大概已经走了。The concert should be great fun. 音乐会应该很有意思。3.should 用于征求意见主要用于第一人称的疑问句形式Should I open the window? 我可以打开窗户吗？Where should I meet you tonight? 我今晚该到哪儿与你见面？What should we do now? 我们现在该干什么呢？4.should 表示谦逊或委婉。通常与 like, lov
7、e, think, say, imagine 等动词连用 I should say shes over forty. 我想他有 40 多岁了。I should think its too expensive. 我看这太贵了。【注】should 表示推断时，语气较肯定，通常是指非常可能的事(因为暗示有一定的事实依据或合乎常理)4I should imagine it will take about three hours. 我想得花大约三个小时。5.should 表示意外或惊讶 Its strange that he should come so late. 他竟然来这么迟真是奇怪。Im sor
8、ry that this should have happened. 我很遗憾竟然发生这种事。6.有时与 why, who, how 等疑问词连用 Why should you think that way? 你为什么会那样想？How should I know? 我怎么会知道？练习：1.Can you dance? Yes, I .A.do B. can C.cant2.Can he write English? No, he .A.can B.cant C.does3.I ride a bike, but I drive a car.A.can, can B.cant, can C can
9、, cant4.She can basketball.A.play B.playing C.plays5.They can play basketball after class.(改为一般疑问句,并作肯定和否定回答.)_they_ basketball after class? 肯定：_,they_. 否定_,they_.6.Lily can sing in English.(改为否定句) Lily_ _in English. 7.完成句子 贝蒂会说英语,但她不会说汉语。Betty English, she speak Chinese.8.那个女孩不会打网球。The girl tennis.9托尼会游泳吗？Tony ? No, he .10.She should reach the station early. 改为否定句She reach the station early.11.完成句子:我要穿大衣吗？5wear a coat?
