Hungry Cows ©™® 

21 Hungry Cows were starving on a street.
The green one said "I'm hungry let's eat."
The 13th saw something ahead.
The stupid cow said: "It might be a bed."
The others realized they were two legs,
The legs of the cow which sometimes laid eggs.
They looked horrified at what they have seen.
But then the legs were eaten by the cow that is green.
They said: "What have you done with the food?"
"We are starving too and you are so rude"
"We don't like rude cows, rude cows like you"
"4 other cows died and you will die too"
"Come on Killer Cow, we have a job for you"
The green cow was scared and she couldn't say more then a "Moo"
Another one dies, but they were still very plenty
They don't like rude cows and now they are 20.