You're <being> quiet today.

[baovsk]

When I want to tell a friend now, what do I say? (He's usually talkative and loud)

You're being quiet today.
You're quiet today.

I think the first one is correct but would it be incorrect to say the second one?

 

[Asirbac]

Hi!

Actually, both are correct. It depends on the person who is talking and it's preferences. For example, the first one sounds better to me, but you can use both. You could use "You seem quiet today", too. This last sentence look more "transitive" to me, because you say that "you look quiet" rather than "being quiet". Using the verb "to be" sounds more permanent and direct to me.

But, anyway, they are all ok! I hope I've helped you!

 

[Roxxxannne]

To me, 'you're being quiet today' is a little more emphatic and 'you're quiet today' is more casual. But both of them depend on the speaker's tone of voice and the mood of the person being spoken to.

 

[lingobingo]

My immediate reaction on seeing this question was to think, no, it’s always said as “You’re very quiet today?”, in an enquiring tone. That’s what I’m familiar with, anyway.