Modals can be combined in certain ways but not in others.
Will and can
Will and can can not be combined. Will can be combined with be able to.- I will be able to tell you tomorrow. - correct
- Will I be able to tell you tomorrow? - correct
- Will can I tell you tomorrow? - incorrect
- I will can tell you tomorrow. - incorrect
Common combinations using be able to
- Might not be able to
- have to be able to
- must not have been able to
- must be able to
- going to be able to
Common combinations using have to
- be going to have to
- shouldn't have to
- should have to
- must not have to
- might have to
Introduction
Polite requests
Expressing necessity & obligation
Lack of necessity
Prohibition
Expectation
Giving advice
Making suggestions
Ability
Expressing preference
Degrees of certainty (present)
Degrees of certainty (past)
Degrees of certainty (future)
Progressive forms
Repeated past
Modal & phrasal verb combinations
Polite requests
Expressing necessity & obligation
Lack of necessity
Prohibition
Expectation
Giving advice
Making suggestions
Ability
Expressing preference
Degrees of certainty (present)
Degrees of certainty (past)
Degrees of certainty (future)
Progressive forms
Repeated past
Modal & phrasal verb combinations
This page is one of PLS's English grammar pages for people who want to learn or improve their English grammar skills.
