1、Unit 3 Teenagers should be allowed to choose their own clothes重点词组：1.get their ear pierced 2.so do we 3.go shopping with sb 4.get to class late 5.talk about sth 6.would like to do7.concentrate on 8.be good for 9.learn from each other10.for example 11.once a week 12.as much as13.achieve ones dream 14
2、.think about 15.be serious about16.practice doing 17.care about 18.be strict with19.get to doing sth 20.Its a good idea for sb to do重点语法：1.“语态”表示主语和谓语动词之间的关系。英语中有“两态”的说法，即主动语态和被动语态，本单元中反复出现的 should be allowed 就是一个含有情态动词（should）的被动语态。2.被动语态的构成含 be 动词的The office is cleaned every day.The office was cle
3、aned yesterday.The office is being cleaned.The office has been cleaned.根据上例，我们可以看出：一般现在时的被动语态为：主语+am/is/are+过去分词一般过去时的被动语态为：主语+was/were+过去分词现在进行时被动语态的构成为：主语+is/am/are+being+过去分词现在完成时的被动语态：主语+has/have+过去分词（2）含有情态动词的情态动词（can/may/must/should ）+be+ 过去分词Teenagers should be allowed to choose their own clo
4、thes.3.被动语态的用法：(1)不知道或没有必要说明动作的执行者是谁Such books are written for children.(2)强调动作的承受者，这时应有 by 短语The cup was broken by David.(3)作客观说明时，常用一种被动语态句型Its/was said/believed/reported+thatIts reported that about three hundred people were killed in this earthquake.据报道，这次地震中大约有三百人死亡。特别注意，在英语中有“十大动词”的说法，即 feel,he
5、ar,listen,have,make,let,look,watch,see,notice,这些词在主动句中，其后的动词不定式不加 to，但变被动句时必须加 to.I saw him go into the office building.He was seen to go into the office building.4.不能用被动语态的几种情况（1）当主动结构中的宾语是反身代词和互相代词时，不能用被动语态We often help each other.(2)当谓语是表状态的及物动词（have,like,take place,belong to）I like these flowers
6、.I will have a meeting.5.twelve-year-olds 相当于 twelve-year-old teenargers,12 岁的孩子数词和一个相应的名词单数用“-”连接起来，可以构成一个合成形容词。常见的还有：two-month hoilday 两个月的假期a sixty-pound stone 一块 60 磅的石头6.get their ears pierced，结构是 get/have+n./pron.+ v-ed,意思是“叫/ 让/请别人做某事I want to get my coat mended.7.allow sb to do sth 允许某人做allo
7、w doing sth 允许做We should allow teenagers to surf the Internet.Be allowed to do 被允许做某事He is allowed to stay up until 11:00 p.m.We should be allowed to take time to do things like that more often.我们应该被允许更加经常的多花些时间多做这类事情。8.主语+seem to do sthHis temperature seems to be all right.否定：He doesnt seem to have
8、 many friends.=It seems that he doesnt have many friends.Seem 的用法： seem +名词/形容词It seems +that 从句That seems a good idea.The question seems quite easy.It seemed that nobody knew anything about the matter.9.So do we.为倒装句，其结构是 so+be 动词/助动词/ 情态动词+主语，在时态上应和上一句保持一致。表示“我们也是这样”He likes oranges.So do we.Tom c
9、an swim.So can John.否定形式：Neither/Nor+be 动词/助动词/情态动词+主语（前为否定） ，表示与前面所述事实不一致。He doesnt like oranges. Neither do we.Tom cant swim. Neither can John.So+主语+be 动词/助动词/情态动词 表示对前面事实的进一步确认。Harry is very tired. So he is.(的确是)10.be strict with+人 be strict in+食物The head teacher is strict with his students.He is
10、 strict in the work.11.the other day(用于过去时) 我们还可以说 the other day,morning,week,month不久前的一天，一个上午，一个星期，一个月I saw him in London the other day.12.concentrate onThis company concentrates on China market.这家公司把重点放在中国市场上。13.Its a good idea for sb to do sth.Its a good idea for us to travel the south.be good fo
11、r 对有好处 有益于This kind of food is good for me.这种食物对我身体有益。Sunshine is good for plants.阳光对植物有益。14.on school nights, on Friday nights, on Saturday afternoons我们在说某个具体的，特定的早晨、下午、晚上时应该用 on15.take time to do sth 花费时间做某事take 在这里为“花费”的意思类似的词组有 It takes some time to do sth (it 为形式主语)It took me 2 hours to finish my homework.
