e/Pluperfect progressive tense

Information
has gloss	eng: The pluperfect progressive tense (or past perfect continuous) is a perfective tense in most Indo-European languages which shows an event that started in the past and continued up until another time in the past. This grammatical tense may be contrasted with the present perfect continuous tense, wherein the duration of the event does not continue up until the present time, but rather stops before another event in the past.
lexicalization	eng: pluperfect progressive tense
instance of	e/Grammatical tense