Paragraphs are an important unit in an essay. Think of them as building blocks for
the architectural structure that is your essay. Each paragraph should develop a new
assertion, not merely repeat that assertion in different words. When you revise a
draft, read your paragraphs to make sure they are coherent: that is, that they contain
only ideas and evidence relating to the topic sentence. In some essays, you may need
more than one paragraph to develop an assertion fully. This group of related paragraphs
is called a paragraph cluster.