YOU SAID:
The dog chased the cat, while the cat chased a mouse.
INTO JAPANESE
猫がマウスを追っている間、犬は猫を追いかけた。
BACK INTO ENGLISH
While the cat chasing mouse dog chased the cat.
INTO JAPANESE
猫ながら猫を追ってマウス犬を追います。
BACK INTO ENGLISH
Chasing the cat while the cat, chases a mouse dog.
INTO JAPANESE
猫ながら猫を追いかけて、マウス犬を追います。
BACK INTO ENGLISH
Chasing the cat while the cat, chases a mouse dog.
That didn't even make that much sense in English.