Grade 9 Grammar Lesson 24 Must and have to

What is the difference between ‘must’ and ‘have to’?
Does ‘must’ have a past form?
Does ‘have to’ have a past form?
What is the difference between ‘mustn’t’ and ‘don’t have to’?

• Both must and have to are used to mean that it’s necessary to do something.
• Must is personal. Must is used when we give our personal feelings.
• Have to is impersonal. We use have to for facts and rules.
• Must doesn’t have a past form but have to has past form had to.

Note: Mustn’t and don’t have to are completely different. Mustn’t means it’s necessary you don’t do something, so don’t do it. Don’t have to means you don’t need to do something but you can if you want.

Go to page 1 2