Level A2

Must: strong obligation and deduction

Must can express a strong obligation or a deduction: must + the plain action word, with no to and no -s (I must go, she must study). Mustn't means not allowed (You mustn't smoke here).

I must go home.

Look: I must go home. Must, then go, with nothing between them.

Forms

• I must go home. — must: I really need to; the action word right after it, plain
• She must study. — with she, must doesn't change, and study has no tail
• You mustn't smoke here. — mustn't: it's not allowed

A common mistake

Wrong: You must to go straight.

Right: You must go straight.

So many people say You must to go, but there is no to after must. We say: You must go straight.

More examples

I must go home soon.

The same here: I must go home soon. No to between must and go.

You must study.

And with you: You must study. Must plus the plain action word.