"must" vs "have to"

[Sultano]

When is MUST used ?

When is HAVE TO used?

Thanks
Sultano

[Yankee]

Hi Sultano

There is a good explanation here

Probably the most common problems for ESL students are:
- using must far too often
- forgetting that not have to and must not have different meanings
- forgetting that the past form of must is had to

Amy
_________________
Amy
.
ESL teacher, translator, and a native speaker of American English

[Sultano]

I must clean the house before mum gets back. I want her to find it all neat and tidy. ( Who decides that it is necessary? )

Sorry, I can't come out now. I've got to tidy up my room before I'm allowed out. (Who imposes the decision?) Are they outer circustances?

He has to attend the clinic every two weeks. He's really quite seriously ill.
You must come and visit us again soon. It's ages since we saw you. ( Who decides that it is necessary? )