Modal Verbs of Obligation Exercise

Fill the gaps with "all" and "every".

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