41.   The problem has been keeping him healthy.

42.   The problem is keeping your favoritism from showing to your kids.

43.   The problem is keeping that talent.

44.   The problems just keep coming for the America Online computer network.

45.   Then he realized that despite all this death and destruction, the same problems keep coming up again, century after century.

46.   Those problems will keep the economy from recovering as quickly as some anticipate, they say.

47.   While all this was happening, a related problem kept getting worse.

48.   A shoulder problem has kept Pierce on the sidelines in recent months but she was heartened by her effort Sunday.

49.   A spokesman for the tribunal said that U.N. financial problems have kept the tribunal from moving any faster.

50.   Back problems kept him out from the U.S. Open until the British Open, but he responded well.