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Modal Verbs Yasamin - Taghizadeh

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Modal verbs of obligation:

Must & Have to : We can use have to, must express

obligation (something you have to do).must + infinitive have to + infinitive

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must is often used when the speaker feels an obligation himself/ herself orwe use must when the speaker feels that something is necessary.

MUST:(strong obligation)

I must study today.I must go to the doctor.

You must exercise . (doctor says) You must be quiet . (teacher says)

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Mustn’t is used to express negative obligation (an obligation not to do something ) Or We use mustn’t to say that sth is a bad idea .

Mustn’t :

You mustn’t drop those glasses . They’ll break . You mustn’t wear your best clothes . You’ll get them dirty .

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Must:

+ : subject + must + verb +….- : subject +mustn’t+ verb+ ….? : no used

Must use in present tense but must has no past tense form , so change to “had to” (past

form of “have to” ).

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Have to is used when the speaker feels an obligation from outside(a rule , law , regulation ) or is just expressing a fact .

Have to :(strong obligation)

We have to(have got to) put the paper to be recycled in the green box .she has to(has got to) buy a newspaper. The boss asked her to get one . * “Have got to” means the same as “have to” but “have got to” is in formal . We use it mainly in the present.

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Negative form : “don’t/ doesn’t have to” means no obligation .

Question form : Do/ Does +subject + have to + verb + ….

Negative And Question Form:

You don't have to eat anything you don't like.I don't have to work on Sundays.

Do I have to do it for Monday ?Does she have to work for Sunday ?

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Have to :

*Present :Have / Has to - don’t/doesn’t have to - do / does … have to*Past : Had to – didn’t have to – did … have to –*Future : • For future with “will” only use “will have

to” not Will must

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"Should" is most commonly used to make recommendations or give advice. It can also be used to express obligation as well as expectation.Examples:When you go to Berlin, you should visit the palaces in Potsdam. recommendationYou should focus more on your family and less on work. adviceI really should be in the office by 7:00 AM. obligationBy now, they should already be in Dubai. expectation

Advice And Recommendation :

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"Ought to" is used to advise or make recommendations. "Ought to" also expresses assumption or expectation as well as strong probability, often with the idea that something is deserved. "Ought not" (without "to") is used to advise against doing something, although Americans prefer the less formal forms "should not" or "had better not.“

Examples:

You ought to stop smoking. recommendation

Jim ought to get the promotion. It is expected because he deserves it.

This stock ought to increase in value. probability

Mark ought not drink so much. advice against something (notice there is no "to")

Advice And Recommendation :

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Should :

+Present , past , future =subject + should +infinitive+…

-Present , past , future = subject + shouldn’t +infinitive+…

? = should + subject +infinitive +…

Ought to :

+Present , past , future =subject + ought to +infinitive+…

+Present , past , future =subject + ought not +infinitive+…

? = ought + subject + to+ infinitive + …

Example : It’s a difficult problem . How ought we to deal with it ?

*after should or ought to we can use a continuous form (be + an –ing form )

It’s half past six already . I should be cooking the tea .

Why are you sitting here doing nothing ? You ought to be working .

Advice And Recommendation :

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We use “had better” to say what is the best thing to do in a situation .

Example :

It’s cold . The children had better wear their coats.

My wife is waiting for me . I’d better not be late .

*we could also use should or ought to in these examples although had better is stronger. The speaker sees the action asnecessary and expected that it will happen .

+had better + infinitive

-had better not + infinitive

Advice And Recommendation :

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Should/ought to have + p.p. verb :We use these forms when someone didn't do the right thing.

Example :

We didn’t play very well . We should have played better .

I got lost .~ sorry . I ought to have drawn you a map .

It was a lovely old building . They shouldn’t have knocked it down .

Advice And Recommendation :

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Assumption/Deduction

deduction/ dɪˈdʌkʃ ə n / noun [ uncountable and countable ] *the process of using the knowledge or information you have in order to understand something or form an opinion, or the opinion that you form : Children will soon make deductions about the meaning of a word.

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Assumption/Deduction

*We use must for logical deduction about the present , when you want to express certainty : It must be very boring to live in a small

village where nothing happens.*The opposite of must in this case is can’t : The letter can’t be from your aunt Harriet

. It’s got a Chinese stamp on it .

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Assumption/Deduction

*Use must have + past participle and can’t have + past participle to make logical deductions about the past : Dave can’t have played football

yesterday . He broke his leg last week .

He must have escaped through this window. It is broken.

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Assumption/Deduction

assumption/ əˈsʌmpʃ ə n / noun [ countable ] something that you think is true although you have no definite proof → assume assumption that A lot of people make the assumption that poverty only exists in the Third World. My calculations were based on the assumption that house prices would remain steady.

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Assumption/Deduction

*Use may have/ might have / could have + past participle to make assumptions that you are not entirely sure about : I was expecting a package today , but

it hasn’t arrived . I suppose I may / might /could have got lost in the post .

- May / might/ could not have + p.p. verb

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Y_T