Transcript modals

MODALS
Form
Modal verbs are followed by infinitives:
I can swim
You ought to learn how to swim
Modal verbs can also be followed by
Have + Third form of the verb ( perfect infinitive )
Or be + verb + -ing ( continuous infinitive )
She must have forgotten about our appointment.
They may be watching the match
* The third singular doesn’t take –s :
He can cook very well
* Modal verbs don’t have –ing forms, past forms or passive
third form.
Negative form:
To form the negative, we use
modal verb + not
( not don’t / modal )
Questions
Inversion of the modal and the subject:
Could you help me, please ?
We never use the modal verbs together:
He must can come.
S + modal
Can and can’t
We use can :
1- to give or ask permission:
You can go there if you like.
Can I leave ?
We can also use be allowed to for permission:
we are not allowed to come home after midnight.
I was allowed to leave the room during the test.
We use could as a past form
She said I could use her pen.
2- To say that something is possible:
Driving at more than 100km/h can be
dangerous.
3- To talk about ability:
I can ride a horse but I can’t drive.
We use could to talk about ability in the past:
I could swim when I was four.
We use be able to to form other tenses for ability:
I have been able to walk across the continent.
I hope I’ll be able to speak English well.
We use can’t :
1- to express prohibition : )‫(منع‬
You can’t smoke on the plane.
2- to say that something is impossible:
Water can’t freeze in the temperatures above 0°C.
3- to express the lack of ability:
I can’t speak Arabic.
* When we talk about the past we use couldn’t:
I couldn’t ride a bike when I was a very young.
The car couldn’t go faster than 70 km/h.
My grandmother couldn’t speak any foreign languages.
can’t
can
1- give
or ask permission
Can I leave?
2- say that something is
possible
1- express prohibition.
You can’t smoke on the plane.
2- say that something is
impossible.
This can be dangerous.
Water can’t freeze in the
temperatures above 0°C.
3-talk about ability
I can ride a horse
3- express the lack of
ability.
I can’t speak Arabic.
could
We use could:
1- to make a request and ask for help:
Could you give me a lift home?
Could you tell Mary to phone me, please?
Could I borrow you’re your newspaper for a moment.
2- to form the past of can( to express ability or lack of
ability)
I could have won the race.
She couldn’t read the article because it was in French.
could
3- to speculate about the past or the present , to say
that something is/ was perhaps true.:
She could be Italian, she speak English with an
accent.
They could have lost our phone number – that’s
why they didn’t phone.
They couldn’t have arrived yet.
could
We use
could
1- to make a
request and ask
for help:
2- to form the past
of can
( to express ability
or lack of ability)
3- to speculate
about the past or
the present , to say
that something is/
was perhaps true.:
Could and was/were able to
*** WE use could and was/were able to to express ability
or possibility in the past:
* We use could to talk about general ability or possibility
to do something in the past:
I could swim when I was four.
We could visit Venice often when we lived in Italy.
* We use was/ were able to to say that we managed to do
something in the past:
I was able to swim across the lake.(it was difficult but I
managed to do it)
Could and was/were able to
Greece was able to beat Portugal in football. (it
wasn’t easy but they did it)
* We use couldn’t or not able to to say that someone
didn’t have the ability or a possibility to do a specific
thing in the past:
The runner wasn’t able to finish the marathon.
We weren’t able to see the solar eclipse.
Could and was/were able to
was/were
able to
could
ability or
possibility in
the past
ability or
possibility in
the past
general ability
or possibility to
do something
in the past:
say that we
managed to do
something in
the past
Can’t and mustn’t
* We use can’t and mustn’t to express prohibition:
You can’t / mustn’t smoke on the premises.
* We choose mustn’t when we talk about our own
decisions, and we choose can’t to report decisions taken by
other people:
You mustn’t leave the class during the test.
( the teacher expresses his/her decision )
We can’t enter the museum without a ticket.
( the museum authorities have made this rule and we’re
reporting their decision )
Can’t and mustn’t
Can’t
Mustn’t
to express
prohibition
to express
prohibition
our own
decision
decisions
taken by
other peopl
Must
We use must:
1- to talk about obligation
2- to speculate about the present or the past, when we
want to express our certainty that something is or was
true:
She must be at home. Her light is on.
Look at them , how happy they are. They must be
enjoying the film.
The ambulance arrived a few minutes after the
accident. Someone must have called them.
Must and have to
1- we use must and have to to talk about obligation:
I must find a job, my parents can’t support me any longer.
I can’t go out now, I have to look after my baby sister.
* We use must when we talk about our own decisions and
we use have to to report decisions taken by other people :
Teacher: You must write this essay for Monday.
( it’s the teacher’s own decision)
Student: We have to write this essay for Monday.
( the student reports the teacher’s decision)
Must and have to
* We can use have to for tenses and forms that are not
possible with must :
I will have to go to bed early tonight.
I hate having to get up early.
**Past obligations are always expressed with had to:
The driver had to show his driving license when the
police stopped him.
In the middle ages people had to travel on foot or on
horseback.
Must and have to
must
talk about
obligation
have
to
talk about
obligation
talk about our
own decisions
to report
decisions taken
by other people
We can’t use
must for tenses
We can use
have to for
tenses
Not have to, not need to, needn’t and mustn’t
We use not have to and not need to or needn’t to express
lack of obligation. These expressions opposites of must
( showing obligation ):
We don’t have to wear a uniform at our school.
You don’t need to take a taxi , there is an excellent
underground connection.
We needn’t study very hard before this exam.
* The past form of needn’t and not have to is didn’t have
to:
We didn’t have to wear school uniforms in primary school.
When I was a child I didn’t have to help with the
housework.
Not have to, not need to, needn’t and mustn’t
We prefer
needn’t when the decision was made
by the speaker himself/herself,
and not need/ have to when the speaker reports
someone else’s decision:
The match starts at 9.30. you needn’t come before
9.00 o’clock.
The police officer says we don’t have to pay for
parking here.
May/might
We use may/ might :
1- when we ask for permission in a polite or formal way:
May I sit here ?
May I ask a question ?
2- when we are not sure if something will happen or not:
I may go out tonight , if I’m not too tired.
We may/might be late, if there is a traffic jam.
The police may not find out the truth.
May/might
3- when we speculate about past or the present, to say
that perhaps something is or was true:
He always sleeps during the day. He may like
working at night.
My mother was awake last night. She may/might be
resting now.
They have never been late before. They might have
forgotten about our appointment.
May/might not and can’t
* We use may/ might not and can’t to speculate about
the present or the past.
* We use may/ might not to say that perhaps something
isn’t or wasn’t true:
He may not have enough money to buy you dinner.
He may not have done the work yet.
* We use can’t to express a strong conviction
that something isn’t or wasn’t true:
You can’t enjoy horror stories?!
She can’t have failed the test, she’s a very good student.
May/might not and can’t
Compare the sentences:
He may not have a lot of money.
(it’s possible that he doesn’t have a lot of money )
He can’t have a lot of money.
( it’s impossible that he has a lot of money. = it’s
certain that he doesn’t have a lot of money)
Should / ought to
We use Should and ought to :
1- to express obligation:
Everyone should learn first aid.
You really ought to apologize.
You shouldn’t watch so much television.
2- to give advice:
You should learn to drive.
You ought to buy a good dictionary.
Should / ought to
* We prefer
shouldn’t to oughtn’t to :
You shouldn’t use a dictionary for this exercise.
* We use should(n’t)/ ought(n’t) to + have + third form
of the verb
( perfect infinitive) to express regrets about the
past
I shouldn’t have asked him to repair the vacuum
cleaner.
They shouldn’t invited everyone from the office.