Hi, teachers!

someone said " Sucks to be you". What does he mean by saying that?

thanks in advance.
Are you sure you heard it right?

As it is, it's hard to say what it means. It's obviously slang.

Did he say, maybe, "It must suck to be you"? That could mean that you are complaining so much about your life that he's teasing you by saying that your life must be very miserable -- that life must be very unpleasant for you.

However, it's hard to imagine exactly what he said. It may have been something else with a different meaning.

Actually, I'm quite familiar with "Sucks to be you" and it means "Oh, you're going through an unfortunate situation. That's too bad. I'm glad it's not happening to me." It is obviously slang, and frankly, not very nice.

It makes NO sense in the context you provided, however. Why would it be unfortunate for the person to ask about the welfare of others??
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The situation is like this. He just got a windfall and he's very happy about that. But When someone asked him if he would help out his ex-wife with that money, he said to the guy "Sucks to be you".
Sorry. I don't know what he meant. I don't hear that expression much, and I don't use it.

Maybe someone else will be able to give you a better answer.

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 BarbaraPA's reply was promoted to an answer.

Typically, "sucks to be you/him/her/them" is a phrase used to describe how you appreciate someone else's position. For example:

"My sister just bought a new car last week and she already has to pay $500 for repairs."

"Really? Sucks to be her."