What is the right way to teach the deaf?

I got this deaf friend and he recently got his special earing aids which allowed him to hear now.(operation involved but finished) And now he's taking speech lessons. But I don't think he's taking it seriously. Like during the lessons he tells the teacher to hurry up because he want to play in his computer. I can't think of any good method on how I can convince him to take it seriously. I tried taking his game terms as an example in sentences but still not working. And when he lies to me about something, I usually get angry at him and give the silent treatment. He soons says sorry but again soon he will do it again. I saved pics in which he said he will stop lying. But even that didn't stop him. Yeah I know we all lie but If I stop doing this then maybe he'll start thinking its ok and end up doing stupid things. So what do you suggest I do to help him? I've run out of ideas.

People are individuals and there's not one way anything will work. Your friend seems a bit manipulative. You can't make him take things seriously. At best you can tell him how you feel. Short and simple usually works.

The silent treatment is apparantly not working as intended. Perhaps you should stop bouncing back to being his friend again until he "payed back" for his mistake in what you'd deem a satisfying manner. Stand strong, and stand up to your self. There's plenty of people to be friends with in the world, sometimes we don't know it because we don't seek others when we have one.