YOU SAID:

when the dog had hats in the cats lap had worm in snake

INTO JAPANESE

犬が猫の膝の上に帽子をかぶっていたとき、蛇には虫がいた

BACK INTO ENGLISH

The snake had a worm when the dog had a hat on the cat's lap

INTO JAPANESE

犬が猫の膝の上に帽子をかぶっていたとき、ヘビは虫を持っていた

BACK INTO ENGLISH

The snake had a worm when the dog had a hat on the cat's lap