Can you write down eight eights so that they add up to one thousand?

I’m tall when I’m young, and I’m short when I’m old. What am I?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.

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

Twice ten are six of us,

Six are but three of us,

Nine are but four of us;

What can we possibly be?

Would you know more of us?

Twelve are but six of us,

Five are but four, do you see?

What are we?

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

How many times can you subtract the number two from the number fifty?

A man calls his dog from the opposite side of a river. The dog crosses the river without a bridge or a boat and manages to not get wet. How is this possible?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?