If you need more help getting started, check out these example expository essays.
Once you’ve shaped your outline into a full essay, get a Kibin editor to hunt down grammar and syntax errors before you turn it in.
For example, "The most effective symbol in the book is the giant billboard because it reminds the reader that someone is always watching." This thesis statement is strong because it provides an opinion and an explanation. It should voice a clear opinion, and should offer a short explanation of that opinion.
It is clear and concise and lets the reader know right away what you plan to argue in the essay. You should be able to find multiple pieces of reliable evidence -- such as dates, scientific research or quotes from the book -- that support it.
You could write a beautiful, well-researched, expertly executed essay on the perils of watching too much television, and it could be the best piece of literature since Steinbeck penned "East of Eden." However, if your instructions asked you to write a five-paragraph expository essay on the symbolism in "The Great Gatsby," then you aren't going to pass.