YOU SAID:
the cool cat was a bad hat
INTO JAPANESE
かっこいい猫は悪い帽子だった
BACK INTO ENGLISH
a cool cat was a bad hat
INTO JAPANESE
かっこいい猫は帽子が悪かった
BACK INTO ENGLISH
a cool cat had a bad hat
INTO JAPANESE
かっこいい猫は帽子が悪かった
BACK INTO ENGLISH
a cool cat had a bad hat
That didn't even make that much sense in English.