need to / don't need to / needn't

Rules

• Rule 1: need to + base verb

  If something is necessary, use need to + base verb. With he / she / it, say needs to. If a noun follows instead of a verb, don't use to.

  Pattern: subject + need(s) to + base verb · subject + need(s) + noun

  Example: We need to leave now.

  Example: My cat needs to eat twice a day.

• Rule 2: don't / doesn't need to

  If something is not necessary, use don't need to (doesn't need to with he / she / it) + base verb. For the past: didn't need to.

  Pattern: subject + don't / doesn't need to + base verb

  Example: You don't need to bring a towel.

  Example: She doesn't need to buy a new bag.

• Rule 3: needn't (no to!)

  needn't = don't need to. It works like a modal verb: the base verb follows without to, and it is the same for all subjects. needn't is mostly British; American English almost always says don't need to.

  Pattern: subject + needn't + base verb

  Example: You needn't worry.

  Example: He needn't come early.

• Rule 4: Questions → Do / Does … need to?

  Make questions with Do / Does; need stays in the base form. Short answers: Yes, I do. / No, you don't.

  Pattern: Do / Does + subject + need to + base verb?

  Example: Do we need to take a jacket? — No, you don't.

  Example: Does he need to sign the paper? — Yes, he does.

Common mistakes

• You needn't to bring anything. → You needn't bring anything. / You don't need to bring anything.

  No to after needn't; but don't need needs to.

• He need to study. → He needs to study.

  he / she / it → needs.

• You don't need to feed the animals. It's forbidden. → You mustn't feed the animals. It's forbidden.

  Not allowed → mustn't; don't need to only means “not necessary”.