(共44张PPT)
Period 3 Discovering Useful Structures
Unit 5 The Value of Money
1. To review the meanings and functions of some modal verbs;
2. To summarize the meanings of the two forms of past future tense;
3. To express modality and talk about future events in the past.
Learning aims
Leading-in
Listen to the song and complete the lyrics.
If I ______ live my life without
you near me
The days ______ all be empty
The nights would seem so long
With you I see forever oh so clearly
I _____ have been in love before
But it never felt this strong
Our dreams are young
And we both know they'll take us
where we want to go
Hold me now
Touch me now
I don't want to live without you
Nothing's gonna change my love for you
You ________ know by now how much I love you
One thing you _____ be sure of
I ____ never ask for more than your love
Nothing's gonna change my love for you
You ________ know by now how much I love you
The world ____ change my whole life through
But nothing's gonna change my love for you
had to
might
ought to
can
ought to
would
will
may
They are called modal verbs. They are used to express ability, obligation, possibility, intension, request, advice, etc.
Grammar ：modal verbs
Ⅰ、定义：情态动词是一种本身有一定的词义，但要与动词原形一起使用，给谓语动词增添情态色彩，表示说话人对有关行为或事物的态度和看法，认为其可能、应该或必要等。
1. 在形式上，情态动词没有实义动词的各种变化，只有could, would, had to, might 等几个过去式，其他情态动词如must, ought to等的过去式皆与现在式同形。
2. 在意义上，大多数情态动词有多个意义。
3. 在用法上，情态动词与助动词一样，须后接动词原形，构成谓语动词。
Ⅱ、基本特征 :
Ⅲ、常见情态动词、其否定式、其缩略形式 :
情态动词 否定式 缩略形式
can
could
may
might
shall
should
情态动词 否定式 缩略形式
will
would
must
had better
ought to
can not/
cannot
can't
could not
couldn't
may not
/
might not
mightn't
shall not
shan't
should not
shouldn't
will not
would not
must not
had better not
ought
not to
won't
wouldn't
mustn't
oughtn't
to
/
Ⅳ、常见情态动词的用法；
1. 表示能力，常译为“会，能”。can表示现在的能力，could表示过去的能力。
He can ride a bike now, but he couldn’t a few weeks ago.
2. 表示可能性。can多用于否定句和疑问句中，但也可用在肯定句中；could表示过去的可能，多用于间接引语中。
That can’t be Mary — she has gone to school.
I told the boss that I couldn’t finish the work in such a short time.
一、can/could
3. 表示请求或允许，译为“可以”。表示此意时，用could语气更委婉。
- Can/Could I borrow your bike
- Yes, you can.
【拓展】
（1）表示惊讶、怀疑、不相信的态度 (主要用于否定句、疑问句和感叹句中)。
Can hard work change a person that much
（2）can亦可表示“有时会”。
You can be very naughty.
1. 表示说话人的猜测，意为“或许；可能”。might表示的可能性比may小。
You’d better take an umbrella. It may/might rain.
2. 用来提出问题，问可不可以。用might时语气更委婉。
Might/May we use your typewriter for a little while
3. 表示“可以”。作此用法时，might是may的过去式。
You may come if you wish.
The boy asked his mother if he might go to play basketball.
二、may/might
1. 表示习惯性动作。will指现在，would指过去。
Fish will die without water.
He would get up early when he lived in the country.
2. 表示请求、建议等。用would比用will委婉、客气。
Will/Would you please pass me that book
【拓展】
表示意愿或意志。will表现在，would表过去。
I will help you if you need me.
He said he would help you if you needed him.
三、will/would
四、shall/should
◆ shall
1. 用于第一人称疑问句中，表示征求对方的意见或向对方请示。
This room is so dirty. Shall we clean it
2. 用于第二、三人称，表示法律等条文中的规定或说话人的决心，给对方的命令、警告、允诺或威胁。
Nothing shall stop us from carrying out the plan.
◆ should
1. 用于第一人称疑问句询问对方的意愿，但语气更委婉温和。
Should I open the window
2. 表示劝告、建议、命令、责任或义务。
No matter who you are, you should observe the law.
3. 表示推测或可能性。
You should be hungry after the long walk.
【拓展】 should还可表示意外、惊讶等，意为“竟会，竟然会”。
It is surprising that he should have made such a foolish mistake.
1. must表示义务、必要性、命令，意为“必须”。否定式mustn’t表示“不准；禁止”。
We must do everything step by step.
2. must表示推测，意为“想必；准是；一定”，只用于肯定句，否定句用can’t。
1) After such a long walk, you must be tired.
2) — My house is near a busy street.
— It can’t be very quiet.
【拓展】 表示与说话人愿望相反、不耐烦的感彩，可译为“一定要；偏偏；非得”。
If you must know, her name is Mary.
五、must/can’t
六、have to的用法
have to表示“不得不，必须”，有人称、时态和数的变化。否定式为don’t have to。
1) There are so many mistakes in his article that he has to rewrite it. 2) You don’t have to buy a gift, but you can if you want to.
【比较】must和have to
表示“不得不、必须”时，have to与must意思上很接近。但must常表示说话人的主观看法；而have to一般强调客观需要。
1) I’m very tired. I must sit down and have a rest. 2) I have to hurry up now. I have a train to catch.
七、ought to的用法
ought to表示“应该；应当 ”，可以表示有责任或有义务做某事。没有人称、数和时态的变化，否定式为 ought not to。
1) They ought to apologize.
2) Such things ought not to be allowed.
3) He oughtn't to have been driving so fast.
【比较】ought to 和should
ought to与should一般来说，两者可以互换，只是ought to的语气略强。另外，表示出于法令规则、行为准则、道德责任等客观情况而“应该”做某事，通常用ought to；若用should则含有个人意见，强调主观看法。
1) You are older brother. You ought to take care of your little sister. 2) You should not waste time in watching TV.
八、had better 的用法
had better，“最好”，缩写为“ ’d better”，表示提出建议、劝告或命令等，含有“应该做某事，有义务做某事”之意，一般适用于对晚辈、平辈。
It's half past two. I think we had better go home.
否定形式为had better not，疑问句中had better的否定形式有两种：
Hadn’t +主语 +better + 动词原形 +...
Had + 主语 + better not +动词原形 +…
1) You had better not talk with strangers.
2) Hadn’t you better go with them
3) Had we better not go
A: Who is knocking at the door
B: It ______ be Tom. He said he would come at this time.
A: It ____ be him. He has gone abroad.
B: It ____ be John, but I am not sure.
A: Who ___ it be
B: Got it It is Mary.
must
can’t
may
can
Read the passage and fill in the blanks with suitable modal verbs in the box .
情态动词表推测：
情态动词+do推测现在或将来发生的动作或状态；
情态动词+be doing 推测正在进行的动作或状态；
情态动词+have done推测过去发生的动作或状态。
1) Tim must have a car now.
2) He must be doing his exercises in the classroom.
3) He must have finished the work, for he is chatting with his classmates happily.
五、情态动词的特殊用法
对肯定、把握性很大情况的推测：
must be /do (现在或将来)
must be doing (说话时正在进行)
must have done (已发生的动作或状态)
对否定情况的推测：
can /could not be /do (现在或将来)
can /could not be doing (正在发生的动作)
can /could not have done (过去的动作或状态)
对不太肯定、把握性不大情况的推测：
may/might (not) be/do (现在或将来)
may/might (not) be doing (说话时正在发生的动作)
may/might (not) have done (已发生的动作或状态)
(1) could/might have done 本来能够做的事却没做
He could have worked out the problem.
(2) should/ought to have done 本来应该做而实际上未做
I really regretted wasting the hours when I should have studied hard, but it was too late.
(3) ought not to have done /shouldn't have done 本来不应该做而实际上做了
I’m very sorry for the words I shouldn’t have said to you at that moment.
Fill in the blanks with suitable modal verbs in the box .
In the film The Million Pound Bank Note, Henry Adams is stuck in
a foreign country without money and friends, and with nowhere to stay.
While this situation ______seem unusual, it can sometimes happen to
travellers. In case it happens to you on a trip abroad, what _______ you
do First, and most importantly, you ______ stay calm. Fear ______
cause you to become confused. You need to think clearly. Second, you
should go to your nearest consulate. They _________ be able to help to
may, must, can, ought to, might, had better, would, should
may
should
must
can
ought to
some extent. Third, you _______ do well to check with some local
charities. They _______ offer help to travellers in need. Fourth, you
____________ avoid getting into trouble. You ______ think that stealing
some money or food would help you, but you should not do so. Getting
caught _______ ruin your life.
would
might
would
had better
might
Work in pairs. Discuss the scene from The Million Pound Bank Note on page 52 and share your understanding of the story. Use modal verbs when necessary.
A: I think it’s kind of Roderick and Oliver to give Henry the money.
B: I’m afraid I disagree. They shouldn’t be making a bet on him.
A: But Henry might get into trouble if they didn’t offer him the money.
B: Well, if they really wanted to help Henry, they could offer him a job.
A: Maybe you’re right. But I guess that would be a different story...
Suggested conversation:
Grammar ：The past future tense
翻译下面含有过去将来时的句子
1．Yes, I was about to go get the letter.
______________________
2．They would leave for Paris the next morning.
_________________________________
3．I was going to help Mary with her Chinese that evening. _________________________________
是的，我正要去拿信。
第二天早上他们将动身去巴黎。
那天晚上我正打算帮玛丽学中文。
一、过去将来时的概念
表示从过去的时间看待将来要发生的动作或状态。即：过去将来时是“立足过去，着眼未来”的一种时态，过去将来时必须有表示“过去” 的参照物，这个参照物是一个发生在过去的动作，而不是时间。常用于主句是一般过去时的宾语从句中。
比较：一般将来时:表示从现在的时间看将要发生的动作或状态。
1．过去将来时的基本构成和用法
过去将来时由“would＋动词原形”构成，否定式是在would后面加not。主要表示从过去某一时间来看将要发生的动作(尤其用于宾语从句中)，还可以表示过去的动作习惯或倾向。
She said that she wouldn’t do that again.
（2022·新高考Ⅰ卷） “ I was afraid that kids from other schools would laugh at him, ” he explained uncomfortably.
二、过去将来时的构成和用法
2．过去将来时的其他表达方法
(1) was/were going to＋动词原形：该结构有两个主要用法，一是表示过去的打算；二是表示在过去看来有迹象表明将要发生某事。
She said she was going to start at once.
It seemed as if it was going to rain.
(2)was/were to＋动词原形：主要表示过去按计划或安排要做的事情。
She said she was to get married next month.
(3)was/were about to＋动词原形：表示在过去看即将要发生的动作，由于本身已含有“即将”的意味，所以不再与表示具体的将来时间状语连用。
I was about to go to bed when the phone rang.
(4)was/were＋现在分词：表示在过去看即将发生的动作，通常可用于该结构中的动词是come, go, leave, arrive, begin, start, stop, close, open, die, join, borrow, buy等瞬间动词。
Jack said he was leaving tomorrow.
三、过去将来时典型错误例析
1. 我们不知道他是否要在会上发言。
误：We didn’t know whether he is going to speak at the meeting.
正：We didn’t know whether he was going to speak at the meeting.
析：该句主句为过去时，且宾语从句表示从过去的某个时间来看将要
发生的动作，所以从句要用过去将来时态。
2. 老师问汤姆长大后准备干什么。
误：The teacher asked Tom what he was going to be when he would grow up.
正：The teacher asked Tom what he was going to be when he grew up.
析：在时间状语从句中，常用一般过去时表示在过去看将要发生的动作。
3. 他们说如果下周日不下雨他们就去农场。
误：They said that they were going to the farm if it would not rain the next Sunday.
正：They said that they were going to the farm if it didn’t rain the next Sunday.
析：在条件状语从句中，也常用一般过去时表示在过去看将要发生的动作。
4. 王林打电话告诉她妈妈，她要买一些书。
误：Wang Lin rang up to tell her mother that she should buy some books.
正：Wang Lin rang up to tell her mother that she would buy some books.
析：过去将来时可以由“助动词should/would+动词原形”构成，但should一般只用于第一人称，而would可用于各种人称。
5. 上次我见到你时，你正打算开始乘火车去西藏。
误：Last time I saw you，you had started to go to Xizang by train.
正：Last time I saw you，you were going to start to go to Xizang by train.
析：表示过去的打算，用过去将来时。
Ⅰ. 完成句子
1.我刚要离开这时我听到有人敲门。
I ____________________ when I heard someone knocked at the door.
2．那天晚上，为了一个重要会议我要飞往上海。
________________Shanghai that night for an important meeting.
was about to leave
I was flying to
3．那时，她会坐在门口看着人来人往。
________________________________, seeing the people back and forth.
4．上个星期天，我们本想去游览长城的，但却下雨了。
Last Sunday we ___________________ the Great Wall, but it rained.
She would sit at the door at that time
were going to visit
【即学即练】
Ⅱ.翻译句子
1．Lily曾说她要到中国来。(would come)
______________________________________
2．有人告诉我他准备回家。(was going to )
_________________________________________
3．他说火车将于第二天早晨六点离开。(was doing )
__________________________________________________
4．她告诉我她要来看我。(was coming)
_____________________________________
5．第二天，他们能完成工作吗？(were going to)
_______________________________________________
Lily said that she would come to China.
I was told that he was going to return home.
He said the train was leaving at six the next morning.
She told me she was coming to see me.
Were they going to finish the work the next day
情态动词
情态动词表特别语气 情态动词表推测 情态动词+have done
can/could 1.能，会2.请求，许可3.怎么会，怎么能（否定、疑问或感叹句） 用于否定句中表示“不可能”、在问句中表示“可能” 否定句：“不可能做了”
肯定句：本来能够做而未做“
must 1. 义务、责任、强制命令2.否定回答needn't/don't have to 3. 偏要，硬要4. mustn't表禁止 用于肯定句中表示“一定、肯定” 肯定句；“一定做了”
may/might 1.表请求 2. may表许可3. may表祝福/愿望 用于否定句或肯定句中，表示“也许” 可能（没有）做过
Summary
情态动词表特别语气 情态动词表推测 情态动词+have done
shall 1,一、三人称问句中表征求意见
2. 二、三人称陈述句表允诺、命令、决心、警告或威胁。
should/ought to 1. 责任、义务（应该，应当）
2. should表惊讶、赞叹或不满 表示“理应、应当”。 肯定句：本该做而未做
否定句：本不该做而做了
will/would 1. 意志、意愿2.征求意见，提出请求3.某种倾向或习惯性动作
need/dare need需要；dare敢于 needn't have done 本不必做而做了
过去将来时
1.“would+动词原形”表示从过去某一时间看将要发生的动作或存在的状态，常用在宾语从句中。
2.“was/were going to do”表示预言、意图或打算。
3.“was/were about to do”表示即将发生的动作。意为“刚要，正要做……”
4.start,come, go,leave,see, meet等用过去进行时表示过去某一时刻就要发生的动作。
5.“was/were to do”表示过去“曾计划做某事”；
“was/were to have done”表示“本来计划做某事，动作没有实现”。
翻译句子
1. 电话响了但是没人接，他一定不在家。
The phone is ringing, _______________________________________.
2. 我找不到我的外套了，我可能昨天落在店了。
I can't find my coat. __________________________________.
3. 真遗憾。你本应该邀请她来参加你的生日派对的。
It's a pity.________________________________________________.
4. 办公室不能抽烟。 __________________________________________.
5. — 他一定要去吗？— 不，不需要。 ________________________________________.
but nobody answers. He can't be at home
I might have left in the store yesterday
You should have invited her to your birthday party
You mustn't smoke in the office.
-Must he go there -No, he needn't.
Exercise
6. 他们问我是否很快要去广州。_______________________________________
7. 他情绪低落的时候，就拉小提琴。
_______________________________________
8. 布朗夫人刚要开始说话，但是珍妮先说话了。
_______________________________________
9. 警察让他赶紧走，但他不要。
_______________________________________
10. 他不知道他以后会出名。
_______________________________________
They asked me if I would go to Guangzhou soon.
He would play the violin when he was in low spirits.
Mrs. Brown was about to speak, but Jenny spoke first.
The police asked him to leave immediately, but he wouldn't.
He didn't know he was to become famous later on.
There's only one corner of the universe you can be sure of improving, and that's yourself.
这个宇宙中只有一个角落你肯定可以改进，那就是你自己。
