Teach Chinese Cantonese for learn English

I am a typical Hong Kong student, native Cantonese, my friends are always picking on my English intonation, and I  am desperate to find a way to change it, can anyone help me with that?? I am pretty good at Chinese,actually it's one of my best subject. I have B grade in HKCEE in Chinese.

I can teach you written Chinese and spoken Cantonese, haha, and maybe a little bit Mandarin, no, not really, I  am not so good at Mandarin =P