This document discusses the differences between sentences, clauses, and phrases through examples. It defines a sentence as a set of words with a complete thought including a subject and predicate, while a clause contains a subject and predicate but is found within a larger sentence. A phrase, on the other hand, is a group of words within a sentence that lacks a subject and verb. The document provides the example "When the rain is over, he ran home quickly" to illustrate an independent clause and dependent clause. It concludes by asking the reader to identify the clause, phrase, and sentence in a short quotation.