Into the pond there are a tadpole and a fish. 

They are friends and they swim together.

One day, the tadpole discovers that he has grown two little legs. 

"Look, I'm a frog" he says. 

"how could you be a frog if last night you were a little fish, just like me. " says the fish. 

They argue a lot and then the tadpole says: "You know what? Frog is frog and fish is fish!"

Days go by and the tadpole grows up. 

And then he climbs out of the water because he becomes a real frog. 

The fish grows up, too, he often thinks: "Where has my friend gone?" 

He is very sad because his friend doesn't come back. 

One day, with a happy splash, the frog jumps into the pond.

"Where have you been?" says the fish.

"I have been around the world, I have seen a lot of things!" says the frog. 

"What have you seen there?" asks the fish.

"Birds, they had wings, two legs and many colours!"

While the frog talks, his friend is imaging in his mind the colourful birds...