The more you take me, the more you leave me behind.
Who Am I?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

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

What have one eye but still cannot see?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

My first is in chocolate but not in ham. My second is in cake and also in jam. My third at tea time is easily found. Altogether, this is a friend who is often around. What is it?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?