21.   Has this ever been done before?

22.   The painters ought to be done before long.

23.   This is what you see Olympic ski racers doing before entering the starting gate.

24.   It took more than twenty years for sales to top one million dollars, which they did shortly before the Civil War .

25.   What did you do before?

26.   She smoked more than she had done before too lighting a cigarette with real hunger when they came out into the sunlight.

27.   No nome could remember it ever being done before.

28.   Calibration of the measuring system was done before the insertion of the probe into the rectum.

29.   It was an operation he had never done before, and it was schrecklich difficult.

30.   This helps them to produce work substantially more creative and thoughtful than what they have been able to do before.