1、Unit 3 Language in use,1. while的用法（1）while用作名词，意为“一段时间；一会儿”。如：I stayed there for a short while.我在那儿待了一小会儿。,（2）while用作连词，有以下几种含义：1）意为“当时；和同时”，引导时间状语从句。如：While I was watching TV, the bell rang.当我看电视时，铃响了。2）连接两个并列句子，表示对比关系。如：He went out for a walk, while I stayed at home.他出去散步了，而我却待在家里。,3）while和when都可以
2、引导时间状语从句，但应注意：while引导的从句中谓语动词必须是延续性动词或表示状态的词；而when引导的从句中的谓语动词既可以是延续性动词，也可以是短暂性动词。当时间状语从句中的谓语动词是延续性动词时，while和when可以互相替换。如：When/While we were talking, the teacher came in. 我们正在谈话时，老师进来了。（talk是延续性动词，when和while可互换）,The bus had left when we arrived at the bus stop.当我们到达车站时，公共汽车已经开走了。（arrive是短暂性动词，when和wh
3、ile不可互换）When/While we were having a meeting, our teacher came in.我们正在开会时，老师走了进来。（have是延续性动词，when和while可互换）,4）while引导的时间状语从句还可以表示某个动作正在进行的同时，另一个动作也在进行之中。如：While the teacher was speaking, the students were listening.老师讲课时，学生们在听。,2. if 引导的条件状语从句（二）（1）含义：从句表示某种假设的情况，主句表示此种情况所导致的结果。（2）时态：从句如果用一般现在时，主句的谓语
4、动词多用一般将来时或“情态动词+动词原形”。如：If you start now, youll finish it before dinner.如果你现在开始（做家庭作业），晚饭前就可以做完了。,She may come with us if she arrives in time. 如果她来得及时，就可以和我们一道去。,（4）若if引导的条件状语从句的主语为you，则可转换为“祈使句+and+简单句”或“祈使句+or+简单句”结构。如：You can pass the exam if you work hard.=Work hard and youll pass the exam.If yo
5、u dont put the meat in the fridge, it will go bad.=Put the meat in the fridge, or it will go bad.,（5）有时，if引导的条件状语从句可以与with或without引起的介词短语互换使用。如：If Linda helps me, I can finish the report soon.=With Lindas help, I can finish the report soon.If theres no water, fish may die.=Fish may die without water
6、.,【话题呈现】本模块围绕“Problems”展开话题，讲述了青少年在成长过程中遇到的一些问题，并提出了解决问题的方法，要求学生能够向他人描述自己生活中遇到的问题，获取解决问题的建议，树立正确的人生观和价值观，并能学会运用if条件句描写某种假设情况。,【佳句荟萃】 I want you to get into the habit of doing your homework as soon as you come home from school.我想让你养成一放学回家就做家庭作业的习惯。If you do all these other things instead of your home
7、work, you wont have time to study.如果你净做这些其他的事，而不是做作业，你就没有时间学习了。You should consider what the most important thing is.你应该考虑什么事情是最重要的。,Thats a shame!真遗憾！If you tell the truth, he wont be angry with you.如果你说实话，他不会生你气的。You spent so much time playing computer games.你花太多时间玩电脑游戏了。My father isnt angry with L
8、ucy any more.我父亲不再生露西的气了。,In my opinion, the Internet is helpful rather than harmful.在我看来，互联网有用而非有害。Smoking is bad for our health.吸烟有害健康。,【写作任务】下面是大明写给他朋友Tom的一封信，信中描述了他的烦恼。请你以Tom的身份给他写一封80词左右的回信，在信中提出他的问题并给出建议。信的开始和结尾已给出，不计入总词数。,Dear Tom,My classmate, Lucy, bought a new pen. I like it very much. So
9、I used it without her permission（允许）. Unluckily, I broke it. Then I put it back secretly（悄悄地）. Now she finds out the truth and is very angry with me. I dont know what to do. Can you help me? Yours, Daming,problem,【写作指导】这是应用文写作，主要内容是讨论问题及提出建议。讨论问题用一般过去时，提建议用现在时。,two,classmates pen,didnt tell her the
10、truth,buy a new pen,offer to pay,sorry,【自主创作】 Dear Daming,I have known your problem.,Yours, Tom,【范文展示】,Dear Daming,I have known your problem. You have made two mistakes. First, you used your classmates pen without her permission. Second, when you broke the pen, you didnt tell her the truth. Yes, you
11、 must tell her immediately. If you tell her the truth, perhaps shell be angry with you, but at least youll prove you are honest.,Then I think you should offer to pay. You can use your pocket money to buy a new pen for her. She will realise that youre truly sorry.I hope the advice can help you. Im sure you will make up with her soon. Yours, Tom,【升格点拨】1. 在给出建议时，使用了First, Second, Then等词使文章条理清晰，有层次感。2. 短语地道，如make mistakes, without ones per-mission, tell the truth, at least, make up等。3. 高级句型“be sure.”和“if条件句”的使用，为文章增添色彩。,
