动词动词表示主语的动作或状态

1、一动词的种类。(1) 及物动词 vt ，其后接宾语。 eg She wears a uniform(2) 不及物动词 vi ，不接宾语。 eg ： She can dance(3) 连系动词 like-v 接表语。 eg They are nursesThat sounds interesting.His mother looks young.If you keep milk for too long, it goes bad (4) 助动词 aux-V 接动词原形或分词 (它无实在意思，只起语法作用)。eg, DO you like pandas?He has gone to Austral

2、ia She is looking at the cat (5) 情态动词 mod-v 接动词原形 (它不能单独作谓语， 有自己的意思， 无人称和数的 变化 )。Eg. He must go now You should clean the classroom after class (6) 有些动词既可作及物动词，也可作助动词或不及物动词，be 也可作助动词。egI do my homework after class (Vt )Do as you like (Vi )She is a little bit quiet (mod-v )She is swimming now (aux-v )

3、 二情态动词的用法(一)can, could, may 的用法l .can could(1) 表示具有某种水平,意为“能,能够,会”(could 表过去 )。eg I can sing English songs Lisa can'tspeak JapaneseShe could swim when she was four years old (2) 表示许：可、允许,意为“能够” 。 eg Can we watch TV now?You can'tplay computer games in the morning (3) 表示请求某人做某事,意为“能,能够”(用 coul

4、d 使晤气更委婉 )。eg CanCould you help me , please?(4) 表示推测“可能” ,多用于否定句和疑问句中。 (表肯定推测可用 must, might , could 等 )eg。it can'tbe true.这不可能是真的。Where can he have gon e?他可能会去哪儿呢 ？2 may might(1)表示许可、允许，意为“能够” ，比 can 更正式。eg. May l use your pen? 我能够用你的钢笔吗 ?May l ask you a question? 我能够问你个问题吗 ?(2)表示推测“可能” ，用于肯定句和否

5、定句，不能用于疑问句。eg. He may be at home now.他可能现在在家。She may n ot be there today .今天她可能不在那儿。(二 )can 与 be able to 的区别1. 两者都能够用来表示水平。eg. I canam able to mend the bike.2. can只有现在时(Can)和过去时(could)，而be able to可用于多种时态。eg. I will be able to come back in another few months.He hasn'tbeen able to get there before

6、 dark.3. can 能够表示推测，但 be able to 不能。eg. That Can't be Gina's dictionary .4. can与be able to;不能重复使用eg.他能做好这件事。He can be able to do is well . (X)He can do it well . (V)He is able to do it well . (V)( 三 )must 与 have to 的区别1. 主客观方面不同。must 表“义务”或“强制” ，表示主观的必要;在肯定句中 must 还可表推测，语气 要比 may 肯定多。 have t

7、o 表“必须”或“不得不” ，表示客观的必要。eg We must clean the room (表示我们认为房间太脏了。)We have to clean the room (表示没有人替我们打扫房间等客观原因。)He must beat home before supper。 (他晚饭前一定在家。 )2. 人称和时态不同。must无人称和时态的变化，一律用must十动词原形。have to后接动词原形，有人称、数和时态的变化，一般现在时的第三人称单数要用has to,过去时中要用had to,将来时中要用 will have to 。另外， have to 还可与情态动词和助动词连用。e

8、g： Tom must practice his guitar every day The train has left We'll have to wait for the next train 3否定式及意义不同。must not=mustn't “决不可千万不可务必不要”; don'tdoesn'tdidn'twon't+have to "不必”eg We mustn'ttell jokes on him 我们千万不可与他开玩笑。We don'thave to tell jokes on him 我们不必和他开玩笑。在对May I? 作否定回答时用 No, you mustn 'can'.eg. May l go to the movies? NO , You mustn't5疑问式及回答不同。Must+主语+动词原形+? Yes,主语+ must./ NO，主语+needn't. 助动词+主语+have to+动词原形+?Yes,主语+助动词./ N