Short clean riddles

Alive without breath, As cold as death; Never thirsty, ever drinking, All in mail never clinking.

What goes up when the rain comes down?

Large as a mountain, small as a pea, Endlessly swimming in a waterless sea.

Every time you stand up, you lose this. What is it?

I'm very, very big. I like to eat peanuts and hay. I have four legs and two big ears. My long nose is called a trunk. I am an...

It is impossible to keep it until you give it someone else. What is that?

Which month has 30 days?

I build up castles. I tear down mountains. I make some men blind, I help others to see. What am I?

Something very extraordinary happened on the 6th of May, 1978 at thirty-four minutes past twelve a.m. What was it?

What is so delicate that saying its name breaks it?