A friend of mine shouted at our teacher and said some dirty words.

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God, that's very wrong. Your friend did the wrong thing. The least he has to do is apologize. What did the teacher do to him? Teachers in general are holy people

He apologized, But I think he's sometimes kind and sometimes arrogant. I think he's too strange to be my friends.

You're friends with him, and you know better. But I don't think you should make too hasty decisions. But if you feel like you don't understand each other, you need to talk about it.