Tense tells you when; aspect tells you how the event unfolds. Aspect is a grammatical category that presents a situation as complete, ongoing, habitual, or having a particular internal temporal structure.

Perfective aspect often views an event as a bounded whole; imperfective aspect views it from inside as ongoing or repeated. English marks progressive aspect with be + -ing and has perfect constructions that relate a prior event to a later reference point. Many languages grammaticalize aspect more elaborately than English does.

Aspect interacts with tense, modality, and the lexical meaning of verbs. Misleading translations often arise when aspect systems differ. Fieldworkers and typologists document aspectual inventories carefully because they shape how speakers package experience in narrative and conversation.

• Grammatical view of an event’s temporal structure
• Includes perfective, imperfective, progressive, and related values
• Distinct from but interactive with tense
• Varies widely in morphological expression