Short, choppy sentences -- if used exclusively -- can make an essay or other writing project seem simplistic or even tedious. To avoid this, writers intersperse extended or complex sentences with shorter sentences. This improves the pacing of a narrative and adds an air of sophistication to an essay.

Combining Equal Thoughts

One way to extend a sentence is to combine thoughts of equal significance using a coordinating conjunction, such as and, but, or, nor or yet. Consider the following example: "Joan went to Victoria College. She earned her degree in business administration." These two sentences of equal significance can be combined using the coordinating conjunction "and": "Joan went to Victoria College and earned her degree in business administration." Another example would be two equal but contrasting thoughts: "Joan went to Victoria College. She dropped out during her second year." These combined thoughts would become: "Joan went to Victoria College but dropped out during her second year."

Combining Subordinating Thoughts

Subordination does not mean something is unimportant; it simply means the thought relies on the main or independent thought to make sense. "When I mow the lawn" is a subordinating thought in that it doesn't make sense unless it is paired with another thought: "I like to make a criss-cross pattern." Making one of the thoughts subordinate to another is a way of extending sentences and avoiding choppy sentence structure. Consider the following two sentences: "I never liked horror movies. They gave me nightmares." They could be combined using subordination: "I never liked horror movies, because they gave me nightmares." A writer can create more stylistic variety by changing the order of subordinating thoughts: "Because they gave me nightmares, I never liked horror movies."