YOU SAID:
I like cats but don't like dogs.
INTO JAPANESE
私は猫が好きだが、犬は好きではない。
BACK INTO ENGLISH
I like cats, but I don't like dogs.
INTO JAPANESE
私は猫が好きですが、犬は好きではありません。
BACK INTO ENGLISH
I like cats, but I don't like dogs.
That didn't even make that much sense in English.