English grammar
Modal Verbs
Modal verbs show what is possible, needed, sure, or allowed. English uses words like can, could, should, must, might, and may in many ways.
Class Modal Verbs
These are the forms taught in English classes all over the world. We show them with real videos, not made-up ones.
Can Do & Allowed To
can / could / may + base verb
We use "can" and "could" to talk about what we are able to do, or to ask for something. "May" sounds more careful. "Could you help me?" sounds nicer than "Can you help me?" Real people know this without thinking.
Rules & Advice
must / should / have to + base verb
"Must" and "have to" both show a strong need to do something. "Must" often comes from you. "Have to" often comes from a rule. "Should" gives advice. This helps you sound natural.
How Sure We Are
must / might / may / could / can't + base verb
These words show how sure we are. "It must be true" (very sure). "It might be him" (maybe true). "She can't be right" (almost never true). The same words can also show ability or rules. The rest of the sentence tells us which one we mean.
Past Modals
should / could / might / may / must + have + past participle
"I must have lost it" (a guess about the past). "She could have called" (she could, but she didn't). "They might have already left" (maybe they left). "It shouldn't have been done" (that was wrong). In real talk, people say "should've", "could've", "must've". This sounds like "of". Some people write "should of" by mistake. Past modals are hard to learn. But people use them a lot when they talk.