In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

John is asked to stand behind Jacob and Jacob is asked to stand behind John. Both of them feel confused about it and don't know what to do?

But it is quite possible, do you know how?

What does a man do only once in his lifetime, but women do once a year after they are 29?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

Can you identify the direction in which this bus is moving; left or right?

Hint: The bus is moving on the roads of London.

By using 'because' continuously three times, can you make an English statement ?

I am dry when I go inside, but wet when I am pulled outside.
The longer I am inside, the stronger I get
When I am completely out, I am wet and I literally sag
Who am I?

What is the word or phrase?