In addition to using different lengths and openings, you can use different types of sentences. Sentences can be classified grammatically and functionally (as discussed in Chapter 37) as well as rhetorically.

Varying grammatical types

Grammatically, sentences fall into four categories—simple, compound, complex, and compound-complex—based on the number of independent and dependent clauses they contain (37f). Varying your sentences among these grammatical types can help you create readable, effective prose.

Varying functional types

In terms of function, sentences are declarative (making a statement), interrogative (asking a question), imperative (giving a command), or exclamatory (expressing strong feeling). Most sentences are declarative, but occasionally a command, a question, or an exclamation may be appropriate.

COMMAND

Coal-burning plants undoubtedly harm the environment in various ways; for example, they contribute to acid rain. But consider the alternatives.

QUESTION

Why would sixteen middle-aged people try to backpack thirty-seven miles? At this point, I was not at all sure.

EXCLAMATION

Divorcés! They were everywhere! Sometimes he felt like a new member of an enormous club, the Divorcés of America, that he had never before even heard of.

Varying rhetorical types

By highlighting sentence endings and beginnings, periodic and cumulative sentences can create strong effects.

Periodic sentences

Periodic sentences postpone the main idea (usually in an independent clause) until the very end of the sentence. They are especially useful for creating tension or building toward a climactic, surprise, or inspirational ending.

Even though large tracts of Europe and many old and famous states have fallen or may fall into the grasp of the Gestapo and all the odious apparatus of Nazi rule, we shall not flag or fail.

—WINSTON CHURCHILL

Look at the following sentence and its revision to see how periodic order can provide emphasis:

Nothing is wrong with the first sentence. But to emphasize the idea in the independent clause—no alternative but coexistence—the writer chose to revise it using the periodic pattern.

Cumulative sentences

Cumulative sentences, which begin with an independent clause and then add details in phrases and in dependent clauses (as does the preceding sentence labeled original), are far more common than periodic sentences. They are useful when you want to provide both immediate understanding of the main idea and a great deal of supporting detail.

I can still see her, a tiny nun with a sharp pink nose, confidently drawing a dead-straight horizontal line like a highway across the blackboard, flourishing her chalk at the end of it, her veil flapping out behind her as she turned back to class.

—KITTY BURNS FLOREY