Hello Cissy,
It is a process!
You will gradually be able to write quicker and more efficiently by practicing writing ,reading and accumulating more vocabulary and expression modes.
Try to 'think English' and avoid translating from your mother tongue,specially that the sentence structure in Chinese is reversely built up in many cases. This will make the translation from Chinese into English very tiresome and time consuming.
You better practice the English structure more through reading and exercising and develop gradually the ability to utilize it automatically.
You should sense the improvement proceeding in small stages.
The more your practice and learn, the quicker your writing will become.
加油!:)