How can you take 2 from 5 and leave 4?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

This is a most unusual paragraph. How quickly can you find out what is so unusual about it? It looks so ordinary, you'd think nothing was wrong with it. Actually, nothing IS wrong with it. But it is not as ordinary as you might think. If you think about it for a bit, you will find out why it is truly so unusual. So what is it? What is so unordinary about this paragraph?

Why Aeroplane windows are round?

What runs around the whole yard without moving?

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

What work can one never finish?

Can you circle exactly four of these numbers such that the total is twelve?

1 6 1
6 1 6
1 6 1
6 1 6

I am looking for a word that change both gender and number when i add the letter 'S'.

What Word am I Looking For ?

Two guards were guarding the camp.Guard-1 was looking towards the south to make sure no threat is coming from the road.Guard-2 was looking at the north to make sure no threat is coming from the top. Suddenly Guard-1 ask the Guard-2 why he is smiling?How Guard-1 knows that Guard-2 is smiling?