It's not difficult to write a good essay, but you do have to learn the basics.  There are some things that every essay must have. Here they are:

Essay structure

Your essay has to follow the English essay structure. In fact, even native speakers of English have to use this essay structure when they write-if they don't use it, then their essay won't be a very good one!  Fortunately, the essay structure is easy to learn. There are only three main parts:

• introduction
• body
• conclusion

Without this basic structure, your thoughts will not be organized and it will be very difficult for the TOEFL assessors to understand your writing.  This is not an exaggeration. The essay structure puts your thoughts and ideas in a logical order.  It arranges your ideas in a way that is natural to native speakers of English.

Thesis statement

Your introduction must have a thesis statement.  This is the last sentence in the first paragraph. It is also the most important sentence in your essay because it tells the reader exactly what your opinion is.  It should be simple and direct. Here are some examples:

   1. Violence on television contributes to violence in society.
   2. In my opinion, studying with a group of people is always better than to studying alone.
   3. My favorite room in the house has always been my bedroom.
 

Topic sentences

Every paragraph in the essay body begins with a topic sentence.  A good topic sentence does two things. First, it gives one reason why your thesis statement is true. Second, it tells the reader what the paragraph is about.  In other words, the topic sentence looks forward and backwards:  it refers to the rest of the paragraph and it refers back to the thesis statement.

Supporting ideas and statements

This is what comes after a topic sentence.  Supporting ideas give specific details and examples related to the topic sentence.  These details and examples could be almost anything:  a personal experience, something you've read, an example from history, a statistical finding, or a philosophical or scientific argument.  Basically, whatever supports your topic sentence can be in the paragraph.
 

Conclusion

This is the last paragraph in the essay.  It is also a very important paragraph.  Put simply, it is a summary of the main points of your essay:  thesis statement + topic sentences.  Of course, you shouldn't copy your thesis and topic sentences exactly.

If you organize your writing by following this essay structure, you will see a big improvement.  All of the essay parts (introduction, thesis statement, topic sentences, supporting ideas, conclusion) work together and not only make your writing stronger, but also make your ideas easier to understand.

William Sullivan