How can a man go eight days without sleep?

An evil man kidnapped someone and made them take one of two pills. One was harmless, but the other was poisonous. Whichever pill the victim took, the kidnapper took the other one. The victim took their pill with water and died. The kidnapper survived. How did the kidnapper get the harmless pill?

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

People make me, save me, change me, raise me. What am I?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Two friends Smith and Andrew were talking about the bravery of their families. Smith told great stories about his courageous grandfather who fought for Britain in "World War I". Andrew told that his grandfather was so brave that in 1919 just after the war he was honoured with a bravery medal with the words "For our Courageous Soldiers In World War I" embedded into it. Smith knows that his friend is lying. How?

How many times can you subtract the number 5 from 25?

How many words can a pen with half refill write?

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?

In a jungle where there are no street lights or any other artificial source of lights, I notice a black snake crossing the road.
How did I get sight of the snake?