Despite extensive research efforts to explain the Mandarin Chinese particle le, confusion persists in the absence of a unitary theory and sufficient empirical evidence. This study provides a unitary account of le by adopting a usage-based constructionist approach, one that liberates grammatical aspect from, and is able to accommodate, lexical aspect. We argue that le participates in two distinct family resemblance constructions of aspect construal associated with two distinct sentential positions. The clause-internal le construction construes the closing or final boundary of an event and the clause-final le construction construes the opening or initial boundary of an event. Corpus analysis showed that the two aspect constructions have distinct patterns in natural language uses that are consistent with the proposed construals. Results from elicited response data showed that native speakers paid attention to construction-level formal and semantic cues in making family resemblance judgments about tokens of the two constructions. This study has both theoretical and methodological implications for crosslinguistic research on grammatical aspect in relation to lexical aspect and for usage-based constructionist approaches to grammatical categories beyond aspect.