YOU SAID:

when your shirt isn't tucked into your pants, your pants are tucked into your shirt ;)

INTO JAPANESE

シャツをパンツに入れないときは、パンツをシャツに入れます;）

BACK INTO ENGLISH

If you do not put the shirt in the pants, put the pants in the shirt;)

INTO JAPANESE

シャツをパンツに入れない場合は、パンツをシャツに入れます;）

BACK INTO ENGLISH

If you do not put the shirt in the pants, put the pants in the shirt;)