Must, Have to, Need to, and Don't Have to

Marco just visited the doctor and is telling his friend what the doctor said. Select ALL the sentences where a modal of necessity is used correctly.

- [x] The doctor said I have to take this medicine twice a day.
- [x] I must stop eating so much sugar.
- [ ] I have to not forget my next appointment.
- [x] I don't have to stay in bed — just rest a little.
- [ ] I need take more vitamins every morning.

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The correct answers are **The doctor said I have to take this medicine twice a day**, **I must stop eating so much sugar**, and **I don't have to stay in bed — just rest a little**.

>"Have to not forget" is incorrect — you cannot place "not" between "have to" and the verb. The correct form is "I must not forget my next appointment" or "I mustn't forget." Be careful: "I don't have to forget" would mean "forgetting is not required" — a completely different (and strange) meaning! "Need take" is missing "to" — the correct form is "need to take." Remember: *need to* always requires "to" before the base verb.
