YOU SAID:

Cats eat dogs; he wanted to make sure they would not eat him first

INTO JAPANESE

猫は犬を食べる彼は彼らは最初彼を食べないことを確認したいです。

BACK INTO ENGLISH

Cat eat dog they would see do not eat him first.

INTO JAPANESE

猫を食べる犬彼らが参照を食べない彼最初。

BACK INTO ENGLISH

Dogs eat cats do not eat they see him first.