YOU SAID:

my dog is a good good dog because he is

INTO JAPANESE

私の犬は良い犬です

BACK INTO ENGLISH

My dog is a good dog

INTO JAPANESE

あいつはいい犬だ

BACK INTO ENGLISH

Dog is a good dog.

INTO JAPANESE

あいつはいい犬だ

BACK INTO ENGLISH

Dog is a good dog.