Translation from russian into english. Must or Have to

Hi my name is Sergey. I have a question.
Here is the sentence in russian:

Посетители девичьего общежития должны ожидать в прихожей.

This sentence needs to be translated into english. I translated it as:

Visitors of the girl dormitory have to wait in the hall.

My teacher says that the best way to translate this sentence into english is:

Visitors of the girl dormitory MUST wait in the hall.

Why in this case must is better then have to?

I’d say “visitors to the girl’s dormitory must wait in the hall”.
I think there’s no significant difference between “have to” and “must” in your sentence. Although I think “must” sounds more “demanding” and formal than “have to” and therefore it should be given preference over “have to” in such imperative sentences as yours.

That said, I don’t understand why your teacher didn’t pick up on your preposition choice. As far as I know “visitors to something” is much more common than “visitors of something”. Also, I believe the term is “girl’s dormitory” or “women’s dorm” and not “girl dormitory”.

I think "have to " is more appropriate.

regards
Pooran

Why is it more appropriate than ‘must’, Pooran?

Because Dear, must denotes something that is abslutely essential to do. here is not like that I think.
that’s why I said have to is more appropriate.
otherwise for more information we have to look for “must & have to” exercieses here.
as you are a teacher maybe you are right & I haven’t learnt the rules of english grammar that well.
if you have points, pls share.
Pooran

Hello Pooran.

‘Must’ denotes command. Here it is a command that the visitor waits in the hall and doesn’t access the dormitory.

‘Must’ is a good choice.