The body of your paper must be coherent and well-written to guide readers through the steps of your argument. Here are some guidelines to help you craft successful body paragraphs.
Topic sentences should appear at the beginning of each body paragraph in your paper. You can think of each one as a mini-thesis dictating your agenda for that particular paragraph.
Keep in mind that each body paragraph should only deal with ONE idea or aspect of your argument. If you're having difficulty introducing a paragraph with a topic sentence, it's likely that you're trying to fit too much into it. Try splitting the material you want to address into logical smaller parts that are more easily summarized in one sentence.
When you finish writing, print out a hard copy of your paper and read it over, summarizing each paragraph in a few words. Your topic statements should closely match what you write down as the central theme of each paragraph.
Since each topic sentence will provide a piece of your argument, the next step is to make sure that you show your readers why each assertion you've made is warranted. Whatever type of evidence you use (textual references, lab results, etc.), you must have something backing up your statements.
It's possible that not every paragraph will require evidence. In some papers, especially longer ones, some paragraphs might simply provide background information or serve as transitions between ideas.
Each paragraph that does provide parts of your argument will likely need evidence. Making assertions without backing them up leaves your work open to criticism. People are not interested in reading a series of unsubstantiated thoughts; they want to know why you've come to the conclusions you have.
Once you've presented your idea and the evidence that supports it, you must explain the connection between the two. While it may seem self-evident to you as the writer, you must remember that your reader might not be as familiar with the material. Analysis serves as a bridge connecting your assertions and your evidence.
If you find that your evidence doesn't need much explanation, it's possible that you'll need to look for more poignant support for your ideas. If you have this problem repeatedly, it could be that your topic itself is not complex enough to allow for sufficient explanation. In this case, you might want to rethink your thesis.
Even if you come up with several paragraphs that have impeccable topic sentences, evidence, and analysis, you're still not finished! Without proper transitions, your paragraphs will not flow together into a coherent whole. Try to connect the ideas in the last sentence of each paragraph with the ideas in the first sentence of the following paragraph.
Feel free to use transitional expressions (i.e. however, therefore, in addition), but try not to overuse them. Too many obvious transitions can actually make a paper feel more fragmented, as they sometimes make it read like an outline. The goal of transitions is to help you segue into your next idea without blatantly announcing it.