1、Unit 2Period 2 Discover Useful Structures学习目标学习目标1.能掌握动词不定式做主语的结构和用法；2.能学会在真实场景中灵活运用不定式做主语的用法。新 课 导 入11.To change bad habits is never easy.2.It took the surgeon three hours to finish my mothers lung surgery.3.To join the Peoples Liberation Army,it is required for men to shave off their beards.4.It w
2、as not polite to disturb your neighbors with loud music last night.Pay attention to the italicized infinitives and discuss the meanings and functions of the italicised infinitives.主语主语主语主语They are all subjects in the sentence.Could you find more infinitives in the reading passage?1.However,during th
3、is period,it can be easy for some of them to form bad habits.2.To prevent harmful habits like these from dominating a teenagers life is essential.3.To change bad habits is never easy,even with many attempts.4.After all,it is not easy to break bad habits.课 堂 学 习动词不定式的时态和语态变化动词不定式的时态和语态变化时态变化时态变化主动式主动
4、式被动式被动式不定式的一般式to do不定式的进行式/不定式的完成式to have done不定式的完成进行式/to be doneto be doingto have been doneto have been doing To be working all day long is a bore.整天干活使人厌倦。(不定式进行式)To have known you is a privilege.认识了你真是荣幸。(不定式完成式)To get up early is necessary.早起是必要的。不定式作主语不定式作主语句首句首单数单数who,whom,whose,what,which,w
5、hen,where,howl How to use the computer is the question.l 如何使用计算机是个问题。l Where to go has not been decided.l 去哪儿还没有定下来。itit作形式主语作形式主语不定式放到谓语的后面不定式放到谓语的后面l Its not easy to work out the problem.=To work out the problem is not easy.l 计算出这道题不容易。l It is interesting to play with snow in winter.l 冬季里玩雪是很有趣的。l
6、 It is terrible to see the ship sinking into the sea.l 目睹轮船沉入大海，真是太可怕了。it作形式主语代替真正主语不定式常见于以下情况中：It is+adj.+for sb.to do sth.It is+adj.+of sb.to do sth.It is+n.+(for sb.)to do sth.It takes/took/will take sb.some time/money to do sth.sb.是to do sth.的逻辑主语,常用于表示事物的特征形容词用来表示不定式的逻辑主语(sb.)的性质、特征或品德动词不定式与动名词
7、作主语时的区别动词不定式与动名词作主语时的区别1.表示一般的、泛指的或习惯性的行为用动名词；表示具体的、一次性的或将来的动作用不定式。Swimming is fun in summer.夏天游泳是有趣的事。To swim in this river is a great pleasure.在这条河里游泳是件非常快乐的事。注意：注意：有时这种区别并不很严格。但要注意：主语和表语要用同一种形式；平行结构中要用同一种形式。To see is to believe.Seeing is believing.眼见为实。2.动名词作主语并不是表示某动作正在进行，而是表示经常性或习惯性的行为；不定式的进行时作
8、主语才表示具体的某一动作正在进行。比较：Its nice having friends to chat to.有朋友聊聊天是很惬意的。(经常性、一般性或习惯性的行为)Its nice to be talking with you here.在这里跟你交谈是非常愉快的。(一次具体的正在进行的行为).单句语法填空1._(travel)along the old Silk Road is an interesting and rewarding experience.2.It is necessary for oceans _(protect)from pollution.3.It is an ho
9、nor for me _(invite)to attend the meeting.4.It is surprising _ Tom to finish such a difficult task in such a short time.5.Its very important _ the new comers to study some rules.6.It is traditional _(bring)a gift to a housewarming party.Traveling to be protected to be invited for for to bring Join t
10、he words to make full sentences.21.important/avoid/passive cigarette smoking It is important to avoid passive cigarette smoking.2.will take/nutrition specialist/a balanced diet menu/make/an hour/for you_ 3.useful/turn to/fitness consultant/for advice _4.illegal/dangerous/take/drugs_5.harmful/skip br
11、eakfast/often _It will take nutrition specialist an hour to make a balanced diet menu for you.It is useful to turn to fitness consultant for advice.It is illegal and dangerous to take drugs.It is harmful to skip breakfast often.Complete the conversations with the correct forms of the phrases in the
12、box.A:Hello,doctor.I want to lose weight,but I just can t seem to do it.What can you do to help me?B:Well,first,its necessary to _ what you eat.Cut out all fatty food and sugary drinks,and eat more fruit and vegetables.A:I really need to _ a way to exercise more.I could use a fitness app,but my phon
13、es full.B.So delete a few files.Im sure the app doesnt take up much space.decide on 3begin with be in control of make a choice decide on make up ones mindbe in control of A:Before exercising,always do a few warm-ups to _B:I know.But then I always feel too tired to continue!A:Should I go for the pizz
14、a or the fried chicken?I hate _ like these.You know whatIm going to eat both!B:Wow!Dont eat too much junk foodyoull get fat.Ive actually _ to go on a diet,so Ill just stick to the fruit salad.making a choice made up my mind begin withbegin with be in control of make a choice decide on make up ones m
15、ind1.To join the Peoples Liberation Army,it is required for men to shave off their beards.要想加入中国人民解放军，男人必须剃掉胡须。shave vi.,vt.&n.剃(须发)；刮脸shave off 剃掉；刮去shave up 剃光shaver n.理发师；电动剃刀The barber _ and a haircut.理发师给他修面理发。gave him a shave2.It was not polite to disturb your neighbours with loud music last n
16、ight.昨晚嘈杂的音乐打扰到来邻居，这是不礼貌的。disturb vt.打扰；搅乱；使烦恼disturbing adj.引起烦恼的；令人不安的disturbed adj.心神不安的；担心的disturbance n.打扰；扰乱；骚动Dont _ the sleeping child.The _ news has made everyone present upset.The drunken man caused a _ in the street.disturbdisturbingdisturbance3.It is useful to turn to fitness consultant
17、for advice.向健身顾问寻求建议是很有效的。consultant n.顾问；高级顾问医师consult v.查阅；商量；向请教consult about 就请教consult sb.on sth.请教某人某事consult with 与商量consult with sb.about a problem与某人就一个问题进行磋商Have you consulted a doctor _ your fever?Before we accept the managements offer we must consult _ the workers again.about with 4.It i
18、s harmful to often skip breakfast.经常不吃早餐是有害的。skip vt.跳过；不参加；悄悄溜走 vi.蹦蹦跳跳地走；跳绳 n.蹦跳skip about 跳来跳去skip along 跳着往前走skip off 溜走，匆匆离开skip out of sb.s way 闪开给某人让路skip over 跳过，忽略，略过skip through 跳读，浏览I skipped _ the first part of the book,eager to get to the exciting bits.She skipped _ without paying her b
19、ill.throughoff5.make up ones mind下定决心Once she has made up her mind,nothing can change it.她一旦下了决心，什么也不能使她改变。在短语make up ones mind中，mind的单复数要随其前ones的单复数而变化。change ones mind 改变主意keep/bear/have in mind 记住；牢记在心头speak ones mind 直言不讳read ones mind 看出某人的心思They have made up their _ to take part.You must keep
20、it _ mind that these exams will affect your final result.The man who has made up his mind _(win)will never say“impossible”.into winminds6.cut out 切去；省略；停止(做某事)Youd better not cut out the important details.你最好不要把重要细节删掉。cut off 中断；切掉；使与外界隔绝cut in(马达或发动机)发动；插话；超车抢道cut down(on sth.)削减，缩小(尺寸、数量或数目)cut up
21、 切碎；使悲伤cut through 开辟(出路或通道)When their children lived far away from them,these old people felt cut _ from the world.Tony,why are your eyes red?I have been cutting _ chilies for the last five minutes.offup7.take up 拿起；开始从事；占据(时间，地方)He did not particularly want to take up a competitive sport.他并不特别想从事竞
22、技体育运动。take down 取下；记下；拆卸take on 雇用；呈现；受欢迎take back 收回；使回想起take off 脱下；起飞；开始成功take in 包括；欺骗；吞入(体内)take over 接管；接任take out 带出去take apart 拆开Some insects take _ the color of their surroundings to protect themselves.on课堂总结课堂总结Introduce how to break bad habits and develop good habits using to do as subject.
