If you say my name, I will no longer exist. What am I?

There are five vowels (a, e, i, o, u) in the English language.
Can you tell us a word that contains all these vowels?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

You enter your friend's room. He is not in his room. Although you see that on the bed there are two dogs, five cats, two giraffes and three pigs. Also, a couple of chickens and ducks are flying in the room.

Calculate the number of legs standing on the floor.

I live in a bowl. I can swim. I have a tail. I also have fins and big eyes. What am I?

I am under you when I am whole.
I shift above you if you remove the first letter.
I come all around you if you remove the second as well.

Can you tell me who I am?

I am the fastest animal but cannot climb the tree. What am I?

The dirtier I get, the whiter I look. Who am I?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?