How do I get my teenage child not to speak english with the horrible cockney accent?
I have news for you. Your boy has two accents: the one he uses among people he needs to impress (such as your friends) and the one he uses among his peer group. Many children brought up in big cities have command of two different accents: one for school and one for home. It’s a question of survival. You don’t say what sort of accent you have, but it’s pretty certain that whatever it is, he can do a perfect imitation of it. Just relax. If he’s hearing good English spoken at home and at school, then he’ll probably settle for that. My sons are both able to talk North London cockney, but never do nowadays. Incidentally, I was amused to see Tony Blair on TV visiting his home constituency and suddenly switching to broad Geordie. As I say, it’s pretty widespread!
