YOU SAID:
How old are you if you turned 20 last decade?
INTO JAPANESE
過去 10 年で 20 歳になった場合、あなたは何歳ですか?
BACK INTO ENGLISH
How old are you if you turned 20 in the last 10 years?
INTO JAPANESE
過去 10 年間で 20 歳になった場合、あなたは何歳ですか?
BACK INTO ENGLISH
How old are you if you turned 20 in the last 10 years?
That's deep, man.