Sentences: Simple, Compound, and Complex Experienced writers use a variety of sentences to make their writing interesting and lively. Too many simple sentences, for example, will sound choppy and immature while too many long sentences will be difficult to read and hard to understand. This page contains definitions of simple, compound, and complex sentences with many simple examples. The purpose of these examples is to help the ESL/EFL learner to identify sentence basics including identification of sentences in the short quizzes that follow. After that, it will be possible to analyze more complex sentence varieties. Simple Sentence A simple sentence, also called an independent clause, contains a subject and a verb, and it expresses a complete thought. In the following simple sentences, subjects are in yellow, and verbs are in green.