Modal Verbs of Obligation Exercise

USE	MODAL VERB	EXAMPLES	NOTES
obligation	have to	María has to go to Rome
	must	You must see a doctor	Must expresses more urgency than have to
		She had to see a doctor	Must is only used in the present simple.
no obligation	don't have to	He doesn't have to go	“It´s your choice”
prohibition	mustn't	You mustn't insult people
recommendation	should	You shouldn't eat so quickly
	ought to	You ought to phone her	Ought to is not used in the negative

Fill the gaps.

It's not obligatory to take a tie. You _______ wear one.
1. don't have to
2. shouldn't
3. mustn't
4. have to
Slow down or we're going to have an accident. You ______ drive so fast.
1. should
2. shouldn't
3. ought to
4. oughtn't to
Billy: Are you going to the party?
Sally: I'm not sure. I _______ go.
1. have to
2. mustn't
3. might
4. don't have to
Where's the toilet? I _______ go.
1. mustn't
2. might
3. have to
4. should
_______ I use your phone?
1. Must
2. Have to
3. Should
4. May
You _________ do your homework on Saturday morning. That way you have the rest of the week-end free.
1. must
2. shouldn't
3. might
4. ought to
You ______ be horrible to your sister. It makes her very sad.
1. shouldn't
2. mustn't
3. must
4. have to
Tomorrow's a holiday. We ________ get up early.
1. mustn't
2. should
3. don't have to
4. have to
You should take an umbrella. It ________ rain.
1. might
2. must
3. has to
4. shouldn't
If you go sailing, you _______ wear a life jacket. The sea is very dangerous.
1. mustn't
2. might
3. should
4. must