You must come/have come from America

[nelson13]

Usually we say that MUST HAVE COME is the past tense of MUST COME(somehow when I am typing this I find it strange....)

context: A woman gets hurt. The woman utters something in American English. A man comes, and says: you must come from America.

I know the situation is in the present, but I think the man should say YOU MUST HAVE COME FROM..., because his sentence gives me the sense that he is saying IT IS NECESSARY THAT YOU COME FROM....

But I am not sure; could anyone help me?

Thank you very much.

 

[5jj]

Usually we say that MUST HAVE COME is the past tense of MUST COME(somehow when I am typing this I find it strange....)

It is not past tense as such. 'Must come' can be, depending on context, (1) an obligation imposed or (2) an expression of present logical certainty about a present situation. 'Must have come' is a present expression of logical certainty about a past situation.

context: A woman gets hurt. The woman utters something in American English. A man comes, and says: you must come from America.

I know the situation is in the present, but I think the man should say YOU MUST HAVE COME FROM..., because his sentence gives me the sense that he is saying IT IS NECESSARY THAT YOU COME FROM....

In this situation, 'it is necessary that you come from' would be meaningless. As an expression of logical certainty, 'must come' makes complete sense. 'Must have come' is possible, but less likely.

 

[Tdol]

If you're talking to someone about their nationality, then must come is the only natural form for me- you're making an assumption about something that is true regardless of where they are. I'd use must have come if they had, for instance, a sticker on their suitcase that tells me they have just flown somewhere from an American airport, which would apply to citizens of other countries.

 

[emsr2d2]

With your first example, where a woman says something using American English, "You must come from America" is entirely correct. If it helps, imagine that he used the verb "to be". He would have said "You must be from America" or "You must be American". He has made a logical assumption.