人教版八年级英语下册《I'll help to clean up the city parks》SectionA PPT教学课件(第3课时)，共32页。ObjectivesTo learn the use of infinitives.To learn to express your intentions to be a volunteer.Grammar FocusI’d like to help homeless people.She decided to try out for a volunteer after-school reading program.You could ask hospitals to let you visit the kids and cheer them up.Mario believes it can help him to get his future dream job.She volunteers there once a week to help kids learn to read.I’m making some signs to put up around the school.动词不定式动词不定式是一种非谓语动词形式，在句中不能作谓语，没有人称和数的变化。基本形式：to＋动词原形，有时to可以省略；否定形式：not＋动词不定式。动词不定式具有名词、形容词和副词的特征，因此可以在句中作主语、宾语、宾语补足语、定语和状语等。一、作宾语动词不定式（短语）可以放在一些动词后面用作宾语，能以动词不定式作宾语的动词有：begin, want, remember, agree, learn, like, decide, fail, pretend, demand, refuse等。二、 作宾语补足语动词不定式作宾语补足语，表示宾语所做的动作，可以用动词不定式作宾语补足语的动词有：tell, ask, want, like, invite, encourage, help等。如：The teacher asked us to read English for half an hour in the morning.The teacher often tells Jim not to spend too much time playing computer games.Please let me help you.但在let, make, see, watch, hear, feel, notice, have等感官听觉动词或使役动词后面作宾语补足语的动词, 其不定式一般要省略动词不定式符号“to”，可以归纳为以下三种句式：1.不可以省略to的不定式作宾语补足语:_x000B_tell /ask / want / would like / wish /suppose / invite /encourage /teach/ depend on等 + sb.+ to do sth. 例如：The teacher told us to come earlier.Her success encouraged me to try the same thing.Her parents wish her to be a teacher.2.省略“to”的不定式作宾语补足语：let / make / have + sb. +do sth. 例如：Let the girl leave here now.The boy made the baby cry.see / watch / hear / notice / feel +sb.+do sth.例如：I saw the students play basketball on the playground yesterday.I often hear the girl sing in the next room.3.可省可不省的: help sb. （to）do sth.例如：I often help my mother (to) do housework.三. 作状语:（1）作目的状语。强调动词不定式所表示的目的时，动词不定式可用in order to或so as to +动词原形，so as to不用于句首。例如：He stopped to have a rest.The bus stopped so as to pick up passengers.（2）作结果状语。例如：He woke up only to find everybody gone.His grandma lived to see the liberation of China.He is old enough to go to school.（3）在某些表示喜、怒、哀、乐等的形容词后作原因状语。例如：I’m proud to have taken part in the competitions.I’m happy to have found many things I can do.动词不定式的否定形式：（1）动词不定式的否定式是直接在to之前加not. 如：Tell them not to play football in the street.（2）省略to的动词不定式的否定式是直接在动词前面加not. 如：Let the boy not go.HomeworkReview the grammar points we learn today. Make some sentences with infinitives.... ... ...关键词：I'll help to clean up the city parks PPT课件免费下载，.PPTX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。