(1) Old Zen riddle : if a policy is announced and no one hears it, is it really announced?

(2) The first answer to the riddle of existence, therefore, is that substance exists, and exists necessarily.

(3) Whatever the answer to the riddle of quantum reality, the correct assessment of the role and meaning of observers in the Universe must await the outcome of the confrontation of the Cosmos with the quantum.

(4) Bilbo's next riddle is answered but he has trouble with Gollum's.

(5) He who knows not how to riddle

(6) He regarded Haley with a critical eye, as if figuring out a riddle .

(7) Her echo bounced from wall to wall, penetrating his ears like an unsolvable riddle .

(8) A set of hypotheses has been suggested to explain this exceptional riddle of fish reproduction, but as yet they remain untested.

(9) The grieving friends of a York man who drowned in mysterious circumstances have launched a campaign to solve the riddle of his death.

(10) Midnight had arrived, but Leander still hadn't figured out the riddle .

(11) Rob's words echoed through my brain, and they sounded like some cryptic riddle .

(12) A prize that I will get if, and only if, I solve the secret riddle .

(13) They were words she could not understand, but still she searched among them for some clue, some answer to the riddle of her life.

(14) Here's a zen riddle : How lumpy must a sauce be before it can be called a vegetable?

(15) The riddle of her death

(16) Riddle me this then

(17) But Grinsell was writing before the invention of radiocarbon dating - surely here was the chance to answer the riddle of the round skull?

(18) But only one asset will help us crack the US interest rate riddle : patience.

(19) She was pleased at herself as if she had just figured out a riddle .

(20) But no one has answered the related riddle : Who wins if both sides bring their voters to the polls in record numbers?