Obligation & Advice
What is the difference between must and have to?
Must = internal obligation (speaker’s feeling); have to = external rule.
Choose the correct modal:
She looks happy. She ______ have passed the exam.
must
Complete:
You ______ have called me! I was worried. (criticism)
should have
Complete: You ______ wear a seatbelt. It’s the law.
must / have to
Choose:
He studied all night. He ______ be tired.
must
Choose the correct modal:
She didn’t come to work. She ______ have been sick.
might / may have
Complete: I’m tired. I think I ______ go to bed early tonight. (personal decision now)
will (decision now) or should (acceptable depending on context; best: will)
What is the difference between may and might?
Might = less certain than may
What does must have + past participle express?
Strong logical deduction about the past
Which modal expresses strong advice?
had better (also should possible but weaker)
Complete:
They aren’t answering. They ______ be at home. (negative deduction)
can’t
Correct the sentence:
He might has forgotten his keys.
He might have forgotten his keys.
Correct the mistake:
You don’t must come tomorrow.
You don’t have to come tomorrow.
Choose the best option:
It’s cloudy. It ______ rain later.
a) must
b) might
c) should
b) might
Complete:
We ______ have taken a taxi. Now we are late. (regret)
should have