Sentence

A sentence is a grammatical unit that conveys a complete thought and typically expresses a proposition, question, command, or exclamation. In many languages, sentences combine a subject with a predicate, though word order and explicit marking vary. In English, sentences usually begin with a capital letter and end with a period, question mark, or exclamation point. An ill-formed sentence lacks grammatical structure or clarity.

Sentence types are commonly described by function: declaratives state facts, interrogatives ask questions, imperatives issue commands or requests, and exclamatives express strong emotion. By structure, sentences range from simple (one independent clause) to compound (two or more independent clauses), complex (one independent clause plus at least one dependent clause), and compound-complex (two or more independent clauses with at least one dependent clause).

Grammatical analysis examines units within a sentence such as subjects, predicates, verbs, objects, and modifiers. Features like tense, aspect, mood, voice, and negation shape meaning and temporal relations. Punctuation helps clarify boundaries and relation among parts of a sentence; end marks, commas, and other signals guide readability and interpretation.

Historically, the term comes from Latin sententia via Old French and English. The concept of a sentence varies across languages; some rely on fixed word order, others on morphology or particles. In linguistics, the sentence is contrasted with phrases and clauses, and it plays a central role in syntax, semantics, and language education.