Can I say "mad for [something] instead of "mad about [something]"?
Native speaker’s answer
Rebecca
When you are describing negative feelings of anger towards something, the expression is always "to be mad about something." When you are expressing anger on behalf of someone else, you can say "angry/mad for you." Ex: How could they be so unfair to you? I'm so angry for you. Ex: I'm mad about my classmate copying my homework and saying it was their own.