11.   Desperately Leith racked her brains, but there was nothing she could tell him, only the truth.

12.   Throughout the silent journey Luce racked her brains, trying, and failing, to come up with any logical explanation for the portrait.

13.   She was wasting time trying to rack her brains, and if there was one thing she hated doing, it was wasting time.

14.   Rachel racked her brains, trying to remember what Jamie had said of him -- ruthless, living only for his ambition.

15.   And I never have to rack my brain to recall what I got.

16.   As all eyes rest on you, you rack your brain for a mega-blockbuster idea.

17.   Adam Stettner racked his brains trying to figure out when it happened.

18.   Advertisers rack their brains to be equally original.

19.   But the real fun is racking their brains to come up with innovative concepts to impress their clients.

20.   I rack my brain for a solution.