牛津译林版八年级英语上册《Wild animals》PPT课件(第4课时)，共16页。May I help you sir?一、情态动词may的用法1. 用情态动词may 表示肯定推测，译为“可能，也许”，通常只用于肯定句与否定句中，相当于perhaps, possibly 或maybe。may not :可能不，表示否定推测eg：The news may or may not be true.这消息也许是真的，也许不是真的.2. may 除了可以表示推测，还可以表示请求，许可，允许，通常用于疑问句中。eg：—May I go now? 我现在可以走了吗？—Yes, you can. / No, you can't.回答时不可用may, might,或could及其否定形式3. 表示必须，必要。must 和have to在陈述句中，must强调说话者的主观想法， have to强调客观需要，意为“不得不”。在疑问句中，回答must引出的问句时，肯定回答用must, 否定回答可以用needn't或don't have to(不必)，一定不能使用mustn't(禁止，不准)。eg：—Must I finish my homework now ?我现在一定要完成作业吗？—Yes, you must. / No, you needn't/don't have to.是的，一定要。/不，没必要。二、动词不定式结构1. eg：Linda wanted to visit the park.Sandy needs to go with them.Millie decided to stay at home.上面例子中主要行为动词后面的动词都采用了“to ＋ 动词原形”的结构，我们把这种结构称为动词不定式(有时可以不带to)。动词不定式没有人称和数的变化，在句子中不能单独作谓语。2. 也有一些动词后面可以跟动名词结构doing sth. , 但是 意义不同。forget to do sth. 忘记去做某事(事情未做)eg：Don't forget to lock the door when you go out.当你出去时别忘了锁门。forget doing sth. 忘记做过某事(事情已做)eg：I forgot washing hands and washed again.我忘了已经洗过手了，又洗了一遍。课堂练习用所给词的适当形式完成句子1．—Must I finish my homework now?—No, you needn't. You may ________ (finish) it this afternoon.2．She agreed_________(let) me go early.3．The students prepare _________ (play) football after class this afternoon.4．She planned __________ (visit) our city this summer.5．Why did you choose _________(sit) in the front of the coach?6．I want ________ (go) to the library this afternoon.7．We hope __________(arrive) around six.8．It's raining hard so I decide ___________ (not go) out.9．The policeman told the children _____________ (not play) football in the street.10．Please ask him _____________ (not watch) TV until he finishes his homework.... ... ...关键词：《Wild animals》PPT课件免费下载，.PPT格式 本作品中主体文字及图片可替换修改，文字修改可直接点击文本框进行编辑，图片更改可选中图片后单击鼠标右键选择更换图片，也可根据自身需求增加和删除作品中的内容，源文件无水印。如认为该内容涉嫌侵权，可通过邮件提出书面通知，我们将及时处理。