21.   Doctors have been puzzling over the cause of the disease for many years now, and they are still no closer to finding a solution.

22.   I am confident a solution can be found.

23.   He put his retirement on hold until he had found a solution.

24.   The boffins of Imperial College in London think they may have found a solution.

25.   They made a fruitless attempt to find a solution.

26.   You can find a solution if you use a little imagination.

27.   This discussion has renewed my hope of finding a solution to the problem.

28.   She finally found a solution to a problem that had defeated many other researchers.

29.   In this example, the conscious mind at the moment of creation knew nothing of the actual processes by which the solution was found.

30.   I found the solution after reading several low-fat cookbooks.