UNIT II: STUDY GRAMMAR

Modal Auxiliaries:

Modal Verbs And Their Meaning

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What are modal verbs?

Modals (also called modal verbs, modal auxiliary verbs, modal auxiliaries) are special verbs which behave irregularly in English. They are different from normal verbs like "work, play, visit..." They are used to indicate modality. They give additional information about thefunction of the main verb that follows it. They have a great variety of communicative functions.

Use of modal verbs:

Modal verbs are used to express functions such as:

1. Permission
2. Ability/unability
3. Obligation
4. Prohibition
5. Lack of necessity/obligation
6. Advice
7. Possibility/impossibility
8. Probability
9. Requests
10. Certainty/uncertainty

Remember

Modal verbs are followed by an infinitive without "to"

Examples:

• You must stop when the traffic lights turn red
• You should see to the doctor
• There are a lot of tomatoes in the fridge. You need not buy any.

Exception:

• You ought to go to the doctor
• You have to stop driving when the lights are red.

A list of modals

Here is a list of modals:

Modal Verb	Meaning	Expressing	Example
must	to have to	100 % obligation	I must stop when the traffic lights turn red.
	to be very probable	logical conclusion (deduction)/certainty	He must be very tired after such enormous work.
must not	not to be allowed to	prohibition	You must not smoke in the hospital.
can	to be able to	ability	I can swim
	to be allowed to	permission	Can I use your phone please?
	it is possible	possibility	Smoking can cause cancer !
could	to be able to	ability in the past	When I was younger I could stay up all night and not get tired..
	to be allowed to	more polite permission	Excuse me, could I just say something?
	it is possible	possibility	It could rain tomorrow!
may	to be allowed to	permission	May I use your phone please?
	it is possible, probable	possibility, probability	It may rain tomorrow!
might	to be allowed to	more polite permission	Might I use your phone please?
	it is possible, probable	weak possibility, probability	I might come and visit you in America next year, if I can save enough money.
need	necessary	necessity	Need I say more?
need not	not necessary	lack of necessity/absence of obligation	I need not buy any tomatoes. There are plenty in the fridge.
should/ought to	used to say or ask what is the correct or best thing to do	50 % obligation	I should / ought to see a dentist. I have a terrible toothache.
	to suggest an action or to show that it is necessary	advice	You should / ought to revise your lessons
	to be very probable	logical conclusion (deduction)	He should / ought to be very tired after such enormous work.
had better	to suggest an action or to show that it is necessary	advice	You 'd better revise your lessons

Modals in the present and past

Generally speaking modals in the past have the following form:

• modal + have + past participle

Example:

• Present:

• You should see a doctor.

• Past:

• You should have seen a doctor

Except for modals that express obligation,ability and lack of necessity:

• Obligation:

• Present = I must / have to work hard. -- Past = I had to work hard.

• Ability:
• Present = I can run fast. -- Past = I could run fast when I was young.
• Lack of necessity:
• Present = You don't have to / needn't take your umbrella. -- Past = You didn't have to / didn't need to take your umbrella.

But pay attention to the difference between needn’t have+ past participle and didn’t need to+ infinitive:

When we say that someone needn’t have done something, we mean that he or she did an action, but that it was unnecessary, or even a waste of time!

Some examples:

‘I needn’t have washed the dishes because there was a dishwasher in the kitchen’

(I washed the dishes, but this was unnecessary because the dishwasher could have done the job)

‘You needn’t have woken me up, I don’t have to go to school today!’

(You woke me up, but this was not necessary because I did not have to go to school today)

In both situations, somebody did an action that was unnecessary.

Didn’t need to+infinitive:

When we say that somebody didn’t need to do something, we are simply saying that the action was not necessary. Perhaps they did the action, perhaps they did not.

Some examples:

‘We went to a restaurant, but we didn’t need to pay for the food because the boss paid.’

(We ate food in a restaurant, and the boss paid, so using our own MONEY was unnecessary – Did we pay? No, we didn’t)

‘I didn’t need to take towels when I went on holiday, the hotel provided them.’

(Taking towels was unnecessary as they were provided by the hotel. Did I take towels? Possibly yes, possibly no. ‘Didn’t need to’ simply means it was not necessary.)

	Modals in the Present	Modals in the Past
Obligation	You must / have to stop when the traffic lightsare red.	You had to stop.
Advice	You should see a doctor.	You should have seen a doctor
Prohibition	You mustn't smoke here.	You mustn't have smoked there.
Ability	I can run fast.	I could run fast. now I am old.
Certainty	He has a Rolls Royce. He must be very rich. He can't be American. His English is terrible.	He must have been rich. He had a big house and an expensive car. He can't have written that poem. He was illiterate.
Permission	Can I go out?	She could drive her father's car when she was only 15.
Possibility	It may / can / could / might rain. It's cloudy.	I guess it may / can / could / might have been Lacy on the phone.
Lack of necessity	I don't have to / needn't buy any tomatoes. There are plenty in the fridge.	I didn't have to / didn't need to buy tomatoes.(I didn’t buy tomatoes.) I needn’t have bought tomatoes. (I bought them, then I discovered that there are plenty in the fridge.)

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