YOU SAID:
your donkey is up a horse
INTO JAPANESE
あなたのロバは馬の上にある
BACK INTO ENGLISH
Your donkey is on the horse.
INTO JAPANESE
あなたのロバは馬の上にあります。
BACK INTO ENGLISH
Your ass is on the horse.
INTO JAPANESE
あなたのお尻は馬の上にあります。
BACK INTO ENGLISH
Your ass is on the horse.
That didn't even make that much sense in English.