11.   Agnes clenched her teeth recognising a dead end.

12.   His teeth were clenched against the cold, and his sleeves were pulled down over his knuckles.

13.   He clenched his teeth fighting waves of nausea as the vehicle jostled its way up the ramps to the MID checkpoint.

14.   Leonora fought for calm, her breath ripping through her chest as she clenched her teeth together to stop them chattering.

15.   Clenching her teeth in disgust, she burrowed her face into the pillow to shut it out until Penry returned.

16.   As she prepared for her third and final qualifying jump Sunday, Marion Jones clenched her teeth and closed her eyes.

17.   Behind my forced smile, my teeth were clenched together so tightly that my jaws ached.

18.   Clenching his teeth and wrapping both hands around the bat, he strides off to home plate.

19.   Everyone assumed I was well-fixed because of my job, and too proud to disappoint them, I clenched my teeth and handed over my credit card.

20.   I saw the muscle working in his jaw as he clenched his teeth.