Imperative sentences give commands, requests, or instructions and are distinguished by having an implied subject (always "you") that is not directly stated. The verb typically comes first: "Close the door!" (you = understood). Imperatives range from direct orders to polite requests and are complete sentences despite lacking an explicit subject.
Recognize that imperatives address the listener and the subject "you" is understood but not spoken. Practice writing imperatives for different contexts, from direct commands to polite requests using "please."
You already know from studying subjects and predicates that every sentence needs both components — a subject naming what the sentence is about and a predicate saying something about it. Imperative sentences appear to violate this: "Sit down" has no explicit subject. But they don't break the rule — they follow a special convention. The understood subject of every imperative is "you," the person being addressed. "Sit down" is grammatically equivalent to "You sit down." The subject exists; it's simply omitted because it's always already known. This is why "Sit down" is a complete sentence while "Ran to the store" is not — the difference is that imperatives have a recoverable subject.
The verb in an imperative is always in its base form — the uninflected infinitive without "to." This is the same form you use with "I" in the present tense: "go," "listen," "close," "be." Compare: "She goes" (indicative, third person) vs. "Go" (imperative, base form). The base form doesn't change for number or person because the subject is fixed — it's always second person, always "you," whether singular or plural. "Go" commands one person or twenty people equally well.
Imperatives span a wide register, from sharp commands to courteous requests. The difference is often just tone and context — "Stop talking" and "Please stop talking" use the same imperative structure. Adding "please" softens the directness but doesn't change the grammar. Negation follows a predictable pattern: "Don't + base verb" ("Don't go," "Don't be late"). Note that unlike negating most sentences — where "not" is inserted after the auxiliary — imperatives without an auxiliary construct negation by adding "do not/don't" at the front. This is because "do" acts as a support auxiliary whenever negation is needed.
One useful test for identifying imperatives in practice: can you add "you" to the front of the sentence and have it make sense? "Sit down" → "You sit down." "Close the window" → "You close the window." If yes, you have an imperative. This test also clarifies why imperative sentences are grammatically complete — they're elliptical forms of full subject-predicate sentences where the subject has been dropped by convention rather than by error. Recognizing them as complete structures matters for punctuation, parsing, and understanding how commands function in discourse.