YOU SAID:
Underwear should be worn on the inside.
INTO JAPANESE
下着は、内側に着用する必要があります。
BACK INTO ENGLISH
You must be worn inside the underwear.
INTO JAPANESE
あなたは、下着の中着用する必要があります。
BACK INTO ENGLISH
You need to wear underwear inside you.
INTO JAPANESE
あなたの中の下着を着用する必要があります。
BACK INTO ENGLISH
You need to wear your underwear.
INTO JAPANESE
あなたの下着を着用する必要があります。
BACK INTO ENGLISH
You need to wear your underwear.
This is a real translation party!