Pronunciation

I try my best to correct my pronunciation, but the progress seems to be slow down. The key is to practice it as often as possible, and try to chat with people in English. Sometimes when I spoke quickly than usual, my friend couldn't understand what I meant. Fantastic, now I speak more slowly than before and try my best to make them understand what I meant clearly. Unfortunately, it seems that my speaking is not fluent as it was. I think I should practice more.

The most difficult pronunciations to me are as follow:
/l/,/n/ and /r/, when they combine with /ou/， like /lou/,/nou/ and /rou/. I can't pronounce them clearly and identify them quickly.
/n/,/m/: When I speak out 'impossible', it likes 'inpossible'. Fortunately, people can understand it in this case, but not match in other case, like 'teen' and 'teem'. I should enhance the /m/ when I pronounce 'teem'.

To conquer this, the best way is to practice, practice and practice. Record what you say out by yourself, listen it carefully and identify what is the difference between them, then practice and record it again, correct it if I distinguish its difference. Next time, when chatting with someone, be care about the pronounce you need to correct. After a short period, it will be much better and you will get the sense of the achievement.