What word begins and ends with an E, but has only one letter?

These types of puzzles are known as charades. What you have to do is find two words that are referred to in the first stanza and the second stanza and put them together to form the third word in the third stanza.

Just for example, if my first refers to 'off' and my second refers to 'ice', then my whole will be office.

My first is present - future's past -
A time in which your lot is cast.

My second is my first of space
Defining people's present place.

My whole describes a lack of site -
A place without length, breadth, or height.

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?

I have no life, but I can die. What am I?

He digs out tiny caves and stores gold and silver in them. He also built bridges of silver and made crowns of gold. They are the smallest you could imagine. Sooner or later everybody needs his help, yet many people are afraid to let him help them. Who is he?

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

You throw me out when you want to use me and you take me in when you don't want to use me.

Who Am I?

What breaks yet never falls, and what falls yet never breaks?

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?