What always comes into a house through the keyhole?

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

What have one eye but still cannot see?

Sally lives in a place where six months of the year is mild summer and the temperature drops significantly the other six months. She owns a lake where there is a small island. She wants to build a house on the island and needs to get materials there. She doesn’t have a boat, plane, or anything to transport them to the island. How does Sally solve this problem?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Can you start the fire using two pieces of wood?

A man dies of old age on his 25 birthday. How is this possible?

John has eleven friends. He has a bowl containing eleven apples. Now He wants to divide the eleven apples among his friends, in such a way that an apple should remain in his bowl.
How can He do it?

John said, "If yesterday was tomorrow, today would be Friday."

When did John make this statement?