1. Modal Verbs by Soledad Morales Sánchez is licensed under a Creative Commons Reconocimiento-
NoComercial-SinObraDerivada 3.0 Unported License.

2. A modal (also modal, modal auxiliary verb, modal auxiliary) is a type of auxiliary
verb that is used to indicate modality –that is likelihood, ability, permission, and
obligation.
Modal verbs are verbs that go before other verbs. They include can, can’t, must,
mustn’t, should, shouldn’t, etc.
They do not take an –s, -ing or –ed suffix.
Modal verbs are always followed by the base form of another verb.
He should do his homework.( NOT: He should does his homework.)
Can/ Can’t
We use can to ask for permission.
Can I go out?
We use can’t to deny permission .
You can’t go out. It`s cold.
Should/ Shouldn’t
We use should to give advice
You should go to the doctor
We use shouldn’t to advice someone not to do something.
You shouldn’t swim in the deep end of the pool.
Must/Mustn’t
We use must to express obligation.
I must tidy my room.
We use mustn’t to express prohibition.
You mustn’t park here.

3. Make negative sentences. Use the modal verbs in brackets.
1.She can’t go out on Monday. (can)
2. I can’t play the guitar. (can)
3. You mustn’t worry. We have prepared everything for the party. (must)
4. Tom shouldn’t walk. (should)
5. I am so sorry. I can’t help you. (can)
6. Peter shouldn’t play football soccer yet. (should)
7. We mustn’t eat sweets! We are on a diet. (must)
Rewrite the sentences and use the modal verbs can, should and must
1. I’d like to go to the party. ________ I go to the party.
2, Don’t talk! You _________ talk.
3. On the plane. You _________ wear a seat belt all the time.
4. I am not good at Mathematics. I ________ answer this problem.
5. You look bad. You ________ go to the doctor.
Complete with the correct modal verb.
1. You _______ clean your teeth.
2. She studies English so she _________ speak English.
3. You _________speak louder in hospitals and libraries.
4. You _________play videogames if you do not finish your homework.
5. Angie has a headache. She ____________ take an aspirin.

4. Answers
Make negative sentences. Use the modal verbs in brackets.
1.She can’t go out on Monday.
2. I can’t play the guitar.
3. You mustn’t worry. We have prepared everything for the party.
4. Tom shouldn’t walk.
5. I am so sorry. I can’t help you.
6. Peter shouldn’t play football soccer yet.
7. We mustn’t eat sweets! We are on a diet.
Rewrite the sentences and use the modal verbs can, should and must
1. Can
2, Mustn’t
3. Must
4. Can’t
5. Should
Complete with the correct modal verb.
1. Must
2. Can
3. Mustn’t
4. Can’t
5. Should