Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online.In linguistics, a sentence is an expression in natural language a grammatical and lexical unit consisting of one or more words, representing distinct and differentiated concepts, and combined to form a meaningful statement, question, request or command. As with all language expressions, sentences contain both semantic and logical elements, and also include action symbols that indicate sentence starts, stops, pauses, etc. In addition, sentences also contain properties distinct to natural language, such as characteristic intonation and timing patterns. Sentences are generally characterized in most languages by the presence of a finite verb, e.g. "The quick brown fox jumps over the lazy dog".