What's up?
"Was ist los?" is a common informal greeting in German, similar to "What's up?" in English. It is used to ask someone how they are or what they are doing. It can also be used to express surprise or concern about a situation.
What's wrong with you?
This phrase is a common way of expressing concern in German, typically used when someone seems to be in a bad mood or is feeling unwell.
Can you tell me what's wrong?
This phrase is used in a situation where one person is trying to understand the problem or issue that another person is experiencing. It's a polite way of asking for clarification.
I do not understand what is wrong.
It's a phrase that someone might use when they are confused about a situation, or when something unexpected has happened and they are trying to understand what has gone wrong.