The Japanese marker _-te-i-_ can have progressive, resultative, and existential perfect readings and has often been regarded as ambiguous. This paper shows that there is no clear evidence that _-te-i-_ is ambiguous. It proposes a monosemous analysis of _-te-i-_ that unifies its multiple readings and shows how progressives and perfects can form a natural semantic class. Within the context of a Discourse Representation Theory, I propose that _-te-i-_ consists of an imperfective operator _-te-_ and a stativizer _-i-_. The imperfective operator (...) _-te-_ takes an eventuality as its argument and outputs a subpart of the eventuality, which precedes a reference time interval. Secondly, a stativizer _-i-_ maps the subpart of the eventuality, i.e. _-te-_'s output, onto a state which overlaps with reference time and whose category is semantically underspecified and is determined via pragmatic inferences. The vague output of the imperfective operator, i.e. whether it is a proper subpart or nonproper subpart of an eventuality, leads to the contrast between progressive readings and perfect readings of _-te-i-_. (shrink)