This document summarizes different modal verbs in English: - Can refers to physical or cognitive ability, or informal permission. - May refers to formal permission, probability, or possibility. - Must refers to obligation, necessity, or deduction. - Mustn't is used to indicate something that is prohibited or forbidden. - Should/ought to refers to advice, recommendation, or moral obligation.

1. Modal Verbs
CAN MAY
(TO BE ABLE TO) ( TO BE ALLOWED TO)
MUST MUSTN’T SHOULD
(HAVE TO) ( OUGHT TO)

2. CAN X MAY
► Can- (PODER)
habilidade física ou
cognitiva; capacidade,
permissão(INFORMAL)
I can run 100 meters in
10 seconds.
Alex can solve all Math
problems.
Can I take you home?

3. CAN X MAY
► Can- (PODER)
habilidade física ou
cognitiva; capacidade,
permissão(INFORMAL)
I can run 100 meters in
10 seconds.
Alex can solve all Math
problems.
Can I take you home?
► May- (PODER)
permissão, (FORMAL);
probabilidade;
possibilidade.
May I take you home?
It may snow tonight.
We won’t go to the beach
today; it may rain.

4. CAN X MAY
► Can- (PODER)
habilidade física ou
cognitiva; capacidade,
permissão(INFORMAL)
I can run fast.
I am able to run fast.
(TO BE ABLE TO)
► May- (PODER)
permissão, (FORMAL);
probabilidade;
possibilidade.
You may enter .
You are allowed to enter.
(TO BE ALLOWED TO)

9. MUST► Must- ( PRECISAR, DEVER, TER DE) obrigação; necessidade;
dedução.
All of us must obey our parents.
You must buy tickets to watch the documentary. It’s not free.
Julia Roberts must be older than her new husband.
Kurt must work every Saturday.

10. MUST► Must- ( PRECISAR, DEVER, TER DE) obrigação; necessidade;
dedução.
All of us must obey our parents.
You must buy tickets to watch the documentary. It’s not free.
Julia Roberts must be older than her new husband.
Kurt must work every Saturday.
has to
doesn’t have to
had to
didn’t have to
need

13. MUSTN’T

14. MUSTN’T
You mustn’t smoke.

15. SHOULD
► Should / ought to- ( DEVERIA) conselho,
recomendação, obrigação moral.
People should / ought to drive more carefully.