I like to imagine a sentence as a boat. Each sentence, after all, has a distinct shape, and it comes with something that makes it move forward or stay still — whether a sail, a motor or a pair of oars. There are as many kinds of sentences as there are seaworthy vessels: canoes and sloops, barges and battleships, Mississippi riverboats and dinghies all-too-prone to leaks. And then there are the impostors, flotsam and jetsam — a log heading downstream, say, or a coconut bobbing in the waves without a particular destination.
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Just as there is no one perfect boat, there is no one perfect sentence structure. Mark Twain wrote sentences that were as humble, sturdy and American as a canoe; William Faulkner wrote sentences as gaudy as a Mississippi riverboat. But no matter the atmospherics, the best sentences bolt a clear subject to a dramatic predicate, making a mini-narrative.