MUST and HAVE TO: what's the difference and how to use them in English

Summary

In this video, Aga explains the subtle differences between 'must' and 'have to' in English, focusing on how both expressions relate to obligation. 'Must' reflects internal motivation, while 'have to' refers to external obligation, like rules or laws. Aga also clarifies the meanings of 'must not' (forbidden) and 'don’t have to' (no obligation). The video includes practical examples and a quiz to test understanding, helping viewers grasp when to use each expression correctly in everyday and formal situations. This lesson is ideal for learners who want to enhance their grasp of English grammar.

Takeaways

• 😀 'Must' and 'have to' both express obligation, but 'must' is often internal, while 'have to' is usually external.
• 😀 'Must' is something you decide to do yourself, whereas 'have to' indicates something required by someone else, like a rule.
• 😀 Example: 'I must learn French' reflects a personal decision, while 'I have to learn French' implies an external obligation, like a school rule.
• 😀 'Must' is more commonly used in formal or written English, while 'have to' is more often used in spoken English.
• 😀 'Must not' means something is forbidden, such as 'You must not smoke on the plane.'
• 😀 'Don't have to' means there is no obligation, but you can do it if you choose, like 'You don't have to pick me up from the airport.'
• 😀 In spoken English, 'have to' is more commonly used than 'must' for expressing obligation.
• 😀 When giving instructions or rules, 'must' is often used, like 'You must fasten your seatbelt.'
• 😀 The sentence 'I must lose weight' indicates a personal decision, while 'I have to lose weight' refers to an external requirement, such as a professional obligation.
• 😀 'Must not' is used when something is forbidden, like 'Dogs must not enter the playground,' while 'don't have to' implies that something is not necessary, like 'She doesn't have to cook dinner.'

Q & A

What is the main difference between 'must' and 'have to' when talking about obligation?

'Must' is used when the obligation comes from the speaker themselves, reflecting personal motivation or decision. 'Have to', on the other hand, implies that the obligation comes from an external source, like a rule or requirement set by someone else.

Can 'must' and 'have to' be used interchangeably in all cases?

Yes, in most cases, 'must' and 'have to' can be used interchangeably to express obligation. However, 'have to' is more commonly used in spoken English, while 'must' is often used in more formal or written contexts.

When do we use 'must' in relation to personal motivation?

'Must' is used when the speaker is expressing an internal motivation or decision, such as 'I must learn French' because they personally want to or have decided to do so.

What does 'have to' imply in the context of external obligations?

'Have to' indicates that the obligation comes from an external source, like a rule or requirement. For example, 'I have to learn French' could mean it is a school requirement, not a personal choice.

What's the difference between 'must not' and 'don't have to'?

'Must not' means that something is forbidden, indicating that the action is not allowed (e.g., 'You must not smoke'). 'Don't have to' means there is no obligation, and the action is optional (e.g., 'You don't have to pick me up from the airport').

How do we express forbidden actions using 'must not'?

'Must not' is used to express prohibition, indicating that something is not allowed, such as 'You must not smoke on the plane.'

What does 'don't have to' mean in terms of obligation?

'Don't have to' means that there is no obligation to do something. It is not necessary, though the action can still be performed if desired. For example, 'You don't have to cook dinner tonight' if an alternative plan is in place.

Which phrase is more common in spoken English, 'must' or 'have to'?

'Have to' is more commonly used in spoken English when expressing obligation, while 'must' is more common in formal or written English.

When is it correct to say 'I must lose weight' instead of 'I have to lose weight'?

'I must lose weight' is used when the decision comes from the speaker themselves, such as personal motivation. 'I have to lose weight' is used when the obligation is imposed by an external force, such as a professional requirement (e.g., a boxer needing to meet weight categories).

Why is 'must not' used in the example 'Dogs must not enter the playground'?

'Must not' is used in this example to indicate a prohibition, meaning that it is against the rules for dogs to enter the playground. The action is forbidden, not optional.