Past perfect: Reword to avoid confusion?

Hi. I think when we see sentences like "He had studied/lived/worked here for four years" it will be uncertain as to (1) whether he lived for four years in the immediate past or (2) some time in the past or (3) terminated (stopped) the activity just before (even though some context is presented, if I am not mistaken). I hope what I said is clear for you to follow. Anyway, please tell me how we could resolve this possible dilemma. As for the example sentence below, should we reword the part underlined like "he left the place where he had studied/lived/worked some time in the past for four years" or "he had studied/lived/worked for four years just before"?

eg,
He left the place where he had studied/lived/worked for four years.