I am very weak in writing essay. Although i got high marks in other subject. I hope you will give me some suggestion. My teacher always scold me for not trying hard. The real thing is I don't really know how to try.
You must be more specific.
What are you having difficulty with when you write? Do you know how to organize your thoughts when you write your essays? Are you making spelling mistakes? Grammar mistakes?
Ask your teacher to be more specific on HOW and WHAT you need to do to improve your writing.