Переделать диалог в косвенную речь :
Peter: I’m very sorry but I got a “two” in Maths today.
Father: Why? Did you understand the teacher’s question?
Peter: Of course I did.He didn’t understand my answer.

Peter said that he was very sorry but he had got a " two" in Maths that day.
Father asked him why he had got it. Father wondered if Peter had understood the teacher's question.
Peter answered that he had. Peter explained that the teacher hadn`t understood his answer.