Oh...I don't think there are any foreigners willing to teach you free here.I can't accept
teaching people free,but maybe someone will consider so.It's so...time-consuming,and
I get nothing back.
You should go to English forums like WordReference and UsingEnglish.com ESL Forum.
There are much more foreigners there.People here are mainly Chinese people,so what
can you expect when you find foreigners on a Chinese web site?
Good luck with your voyage!