Some languages, e.g., Russian (1), Bulgarian (5) or Greek, show perfective readings of morphosyntactically imperfective verbs:
(1) Jakov ezdil na more dvazhdy za poslednij god.
J. rode.IPF on sea twice in last year
'During the last year Jacob twice went to the seaside.'
The reading in (1) is unambiguously existential perfect. What are the possible semantic mechanisms that cause such effects?
I'm thinking maybe it's the temporal adverbials that introduce the perfective aspect. But they don't just do it by themselves:
(2) Jakov ezdil (*za) dva chasa.
J. rode.IPF (*in) two hours.
'Jacob rode {for, *in} two hours.'
How do the two adjuncts in (1) collaborate to produce the effect? Are there some implicit operators that do the job under certain conditions? I suspect that there is a certain projection (Perf) playing a role, but I can't figure out the details. If there's literature that addresses the question directly, please point me to it.
To give a pair without motion verbs:
(3) Jakov chital lekcii dvazhdy za poslednij god.
J. read.IPF lectures twice in last year
'During the last year Jacob twice gave a lecture.'
(4) Jakov chital lekciju (*za) dva chasa.
J. read.IPF lecture (*in) two hours.
'Jacob read the lecture {for, *in} two hours.'
And an example from Bulgarian (from Iatridou, Anagnostopouluo & Izvorski (2001) Observations about the form and meaning of the Perfect):
(5) ženata običala Ivan ot 1980 nasam
woman.DEF love.IPF.PT I. from 1980 till.now
'the woman who has loved Ivan since 1980'