Learn Can / Can't for Ability and Permission in English
Express ability, inability, and permission with can and can't.
- Learning goal
- Recognize and use this pattern in context.
- Practice
- 10 randomized questions with explanations.
- Suggested workflow
- Study the examples, then take the quiz.
Grammar Focus
Can and can't are modal verbs that English speakers use every day to talk about what is and isn't possible. At the beginner level, you will use them mainly in two ways: to express ability (what someone is able to do) and to express permission (what someone is allowed to do). Both uses follow exactly the same grammar rules, which makes can one of the most learner-friendly modals in English.
- Use can to say that someone has the ability to do something: "She can swim very well."
- Use can't (or cannot) to say that someone lacks the ability: "I can't play the piano."
- Use can to give or ask for permission: "You can use my phone if you need to."
- Use can't to say something is not allowed: "You can't park here."
- Can never changes form — it is the same for I, you, he, she, it, we, and they.
- The verb after can / can't is always in the base form — never add -s, -ing, or -ed.
Form & Structure
Ability & Permission
Inability & Prohibition
Asking About Ability / Permission
Common Mistakes
Adding -s to the verb after can for third person singular
Tip: After can or can't, always use the base form of the verb. Never add -s, even for he / she / it.
Using to after can
Tip: Unlike many verbs, can is followed directly by the base verb — no to in between.
Confusing can't with don't / doesn't for general habits
Tip: Can't implies a physical or situational inability. For personal choices or preferences, use don't / doesn't instead.