Transcript MODALS - INTRODUCTION

MODALS - INTRODUCTION
MODAL VERBS can, could, may, might, must, ought to, shall,
should, will and would:
• are always used before another verb in its infinitive form
without to: He can swim.
• never change – they do not add –s, or –ed or –ing.
• are immediately followed by not in the negative:
You should not (shouldn’t) be late.
• go immediately before the subject in a question:
Could you wake me up?
OBLIGATION AND NECESSITY
• PRESENT: must and have to
I must/have to go now or I’ll miss the bus.
• We only use must in the present tense. In all other tenses we use
have to:
I had to work every day last week. (past simple)
I will have to work longer hours. (future)
• When something is unnecessary we use don’t have to, or needn’t
(NOT mustn’t):
You don’t have to / needn’t take your shoes off inside, but you can if
you want to.
• Mustn’t is a prohibition (when it’s wrong to do it, it isn’t allowed): You
mustn’t smoke inside.
ADVICE
• You should / ought to start looking for a job.
• Should and ought to mean the same but we use should more than
ought to, especially in negative forms and questions:
They shouldn’t let their children watch that.
What should I do?
• When we talk about the past , we use
should + have + past participle
I should have told the truth (= it was a good idea but I didn’t)
ABILITY
•
How many languages can you
speak?
•
CAN - present ability
•
He could read when he was
three.
•
COULD - past ability in general
•
WAS/WERE ABLE TO or
MANGED TO – specific
occasion in the past (not
COULD)
•
WILL BE ABLE TO – future
ability
•
•
She was able to finish on time.
She managed to finish on time
•
You will be able to operate the
machinery at the end of this
course.
DEDUCTION: CERTAINTY AND POSSIBILITY
• I haven’t seen the neighbours
all week. They must be away.
• MUST – certainty
• The man in the photo can’t be
Peter because he never wears
a hat.
• CAN’T – impossibility
• The letter might be / may be /
could be from Tony.
She might come and see you
tomorrow.
• MIGHT / MAY / COULD –
present and future possibility
• Ed may not know how to find
our house.
• we use MAY NOT and MIGHT
NOT in negative sentences,
not COULD NOT
TALKING ABOUT THE PAST
• I can’t find my keys. I must
have left them at home.
• He can’t/couldn’t have got
there yet because it will take at
least two weeks.
• MUST / CAN’T / COULDN’T
HAVE + PAST PARTICIPLE –
when we are certain about the
situations in the past
• I’m not sure what sort of bird it
was that I saw, but it
may/might/could have been an
eagle.
• MAY / MIGHT / COULD HAVE
+ PAST PARTICIPLE –
possibilities in the past