Lesson 17
Always young
Listening to the tape and answer the questions:
What is my aunt? How old is she? What does she wear in her new play? What does she answer if anyone asks her age? Which singer do you think looks younger than his/her age? Would you like to be always young? And why? Do you like to guess others age or not?
Must
1.表达义务，≈ have to 必须
must
强调主观 I don’t like it. I must leave. 单一时态 不能用于will和shall 后
have to
强调客观 It’s late. I have to go 时态丰富 have to / had to/ will have to
Now
Does she look young?
16 years ago
Do you think how old she is? She must be at least……
at least
at + ( the ) + 最高级——表示“最”， “至” at least 至少，最少，起码 at most 至多，最多 at first 最初，首先 at last 最后，终于

Key structures 情态动词must
must 必须 have to have got to 主观 客观 客观
现在must do 表推测 过去must have done

eg. 你必须少抽些烟。 You must cut down on smoking. I’m afraid I must go now. eg. Must you leave now? Yes, I must./ No, I needn’t.
discussion
1.How old is your mother/father? 2. Do they look young? 3.Does your mother have any good way to stay young? 4.Do they do a lot of exercises? 5.Do they use any cosmetics【kɔz'metiks] (化妆品）? 6. Do you have any good suggestions for staying healthy?

Key structures
have to有人称、数、时态的变化，而must没有eg.
I had to go to see the dentist. She had to go shopping yesterday.
在否定结构中： don‘t have to 表示“不必” mustn’t 表示“禁止” eg. You don‘t have to tell him about it. 你不一定要把此事告诉他。 You mustn‘t tell him about it. 你一定不要把这件事告诉他。
orange colored
n.+ed=adj.
a pair of high-heeled shoes 一双高跟鞋 a white-haired doctor 一个白发苍苍的医生 a honey-mouthed boyfriend 一个甜言蜜语的男友

sock n. 短袜 Old socks =buddy老兄 Pull up your socks！ 【谚语】 鼓起劲来！
My aunt Jennifer This time In the play
Last year
When being asked She answered: how old she is
a girl of seventeen
Darling, it must be terrible to be grown up!'
否定表示不允许 mustn’t 非其否定回答
否定表示不需要 needn’t ，don’t have to

Must
2. 表达推测 must+v. (原) 表示对现在情况的肯定推测
e.g. Mary must have some problem:
She keeps crying.
take part in：join, enter for
a girl of 17：a 17-year- old girl What does a girl of 17 look like? What will she wear?
Special difficulties
dress：” 女服 ” “ 女礼服” suit: “ 男装 ” “ （一套）衣服 ”
at the earliest 最早
at the latest 最晚
e.g. There can be no more than fifty people in the audience at ( the ) most. At least two hundred have left.
2.This time,_____ _______a girl of seventeen. she will be
In she must in a 3.___ the play,_____ _____ appear ___ __ bright red and dress _____ long black stockings.
in another she st year___ ________ play, ____had to wear short and a socks ____ ___bright,orange-coloured dress. 2.___anyone_____asks____how old____ ___, ____ _______ If ever her she is she always it must be to be answers,‘Darling,___ ________terrible______grown up!’
must+have+done 表示对过去情况的肯定推测
e.g. I called very loud. He must have heard me.

Must
3. mustn‘t 表示禁止
e.g. You mustn't smoke here.
4. 表示抱怨 e.g. Why must it rain again on Sunday ?
costume: 在特别场合下穿的衣服，如戏服， 化装舞会上的服装 e.g. All the actors wore the
fifteenth-century costumes

Last year in another play, she had to wear short socks and a bright, orange-coloured dress. If anyone ever asks her how old she is, she always answers, 'Darling, it must be terrible to be grown up!'If anyone ever asks her how old she is,
prep. = in the position of 作为 e.g. He works as an engineer. He works like an engineer. conj. = because 因为 e.g. I cannot come as I am busy. = at the time when e.g. As I was leaving the house , the postman brought a letter.. = in the way that 按照…的方式 e.g. Do as you are told.

Key structures
must与have to一般可互换，但表示 “必须” 时， must着重说明主观看法， have to比较强调客观需要。
eg. I must tidy up the room. 我必须打扫一下房间。（主观想法） I have to tidy up the room. 我不得不打扫一下房间。（客观需要）
in：穿…衣服 bright red：亮红， dark green? stocking：亮红， long socks
1._____ aunt Jennifer___an actress. My is
thirty-five 2.____ _________at least __________ years old. She must be
3.In spite of this,____ ______appears____ she often on
as the stage ___a young girl.
a new play soon 1.Jennifer____ _______take part in__________ _____. will have to

My aunt Jennifer is an actress. She must be at least thirty-five years old. In spite of this, she often appears on the stage as a young girl.