✔ 最佳答案
Most people say it rains Cats and Dogs, but I think either ways are same. People still able to understand both mean [heavy rain].
This phrase's origin is unknown. Possible explainations include: The archaic French catdoupe is a waterfall or cataract, lightning and thunder sounds like that of a cat/dog fight, cats had a big influence on the weather, and the sky dog Odin was attended to by wolves according to Norse Mythology.
Another theory is that in old England, they had hay roofs on their houses and the cats and dogs would sleep on the roof. When it rained, the roofs got slippery and the cats and dogs would slide off of the roofs. There for it was "Raining Cats and Dogs".
I hope this one can help you!