YOU SAID:
Dog's are my favorite animal. I love them.
INTO JAPANESE
犬は私のお気に入りの動物です。彼らが大好きです。
BACK INTO ENGLISH
The dog is my favorite animal. I love them.
INTO JAPANESE
その犬は私の好きな動物です。彼らが大好きです。
BACK INTO ENGLISH
The dog is my favorite animal. I love them.
That didn't even make that much sense in English.