YOU SAID:

Where did i leave my underpants?

INTO JAPANESE

私はどこでパンツを去ったのですか？

BACK INTO ENGLISH

Where did I leave the pants?

INTO JAPANESE

どこでパンツを去ったのですか？

BACK INTO ENGLISH

Where did you leave the pants?

INTO JAPANESE

あなたはどこでズボンを去ったのですか？

BACK INTO ENGLISH

Where did you leave the pants?