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

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Replace the question mark in the picture below.

If you’ve got me, you want to share me; if you share me, you haven’t kept me. What am I?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

How many words can a pen with half refill write?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

Can you make a six-letter word using the letters N, A and B ?