Im going to china at the end of March what kind of clothing should I bring? what items should i pack

I think you can just tell you in general, because China is so big. It is still a little bit cold in north part of China, while it is becoming warm in south part of China in March. Generally speaking, you need to take a thick coat, thin sweaters and T-shirts.
For other items, I think you can just take some daily used necessary articles, because I think you can buy most of articles you want in China.