31.   If only we knew their secret.

32.   I know the secret to the best oatmeal cookies in the world.

33.   If you want to know the secret for the trick, you have to call up a text box, which covers the video screen.

34.   If you want to know the secret, go to a plant swap in Flora.

35.   Interiors designers, paperhangers, painters and artists have long known the secret to camouflaging the mundane appearance of plastic wall switch plates.

36.   Justin, however, said he knows a secret about Shere Kahn.

37.   Kate Spence, a British Egyptologist, says she knows the secret.

38.   Oliver, however, knew the secret.

39.   Sometimes people want to know the secret to guitar-making.

40.   Sometimes everyone knows the secret, says family therapist Evan Imber-Black, director of family and group studies at Albert Einstein College of Medicine in New York.