It was twenty years ago before(改为that:强调句) he returned to which(改为where引导宾语从句) he was born and brought
就在20年前,他回到了生他养他的地方.(强调句的)
正常语序:
Twenty years ago,he returned to where he was born and brought up.
也可以说:
Twenty years ago,he returned to the place where he was born and brought up.
returned to the place where(用where不用which) he was born and brought up,