a mystery in English:

Their marriage is a closed book now.

Chemistry is a closed book to me.

Let's try to solve the riddle.

This riddle is driving me crazy.

What is your riddle?

Oedipus had answered the riddle correctly!

The Sphinx had eaten hundreds of people on their way to the city of Thebes, because they could not answer the riddle the cunning Sphinx had asked them.

Don't leave the riddle.

I will let you pass safely, the Sphinx said, "if you can answer my riddle."

I finally penetrated the meaning of the riddle.

Welcome to the best choice of hard riddles and free brain teasers online.

If he could not answer the riddle, he would be eaten.

Still a riddle wrapped in a mystery inside an enigma.

Scientists may have solved the riddle of Saturn's rings.

The story of the sphinx's riddle first occurs in the Greek tragedians

I have a riddle for you.

How much we still have to pay for peace is a riddle.