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.