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the past; bygone days
one's past (that one would prefer remained secret)
past (tense); preterit; preterite
previous life
過去の経験を生かしたいです。
I want to make use of past experience.
彼は犯罪に手を染めた過去を必死に隠して生きてきた。
He has lived desperately concealing a past in which he was involved in crime.
過去のことは忘れて前を向きましょう。
Let's forget about the past.