When you are trying to improve your writing, it's helpful to think carefully about the structure of your paragraphs.  The structure you use will depend on your assignment, and whether your paragraph is part of a longer piece of writing.  This document suggests some of the paragraph structures you might wish to use.

It is important to read over your paragraphs when you have finished writing, to check for spelling and grammar errors.  This document also contains advice on how to check the structure of your paragraph.