(1) documentation, documentation and documentation, including: comment in the code with your name and date, upload/backup the code regularly to a personal netdrive within your company(don't copy any code outside your company), email and cc to your superviosr on a regular basis(no more than one week), such as with all procedure/function/package you've done last week, your plan for this week, etc.
(2) Improve your English, writing and oral, try to do some presentation if possible; I know it's hard and may take a little longer time, but you have to overcome it, sooner or later;
(3) Be positive, at least be professionally, business is just business.
You may have more opportunities to prove yourself. Just don't give up, be happy and positive.
If all the above has no effect, thinking about moving on, for your already has enough experience here now.
My 2 cents.
(sorry can't type Chinese at work)