21.   Neither the participants nor the researchers knew what drug the participants were taking.

22.   Only five participants take part in each session.

23.   Participants take a running start, then throw themselves on the thin, yellow mat attached to a floatlike blue section, all kept slippery by a sprinkler.

24.   Only a random sample of pupils takes the federal test, and each participant takes only some questions, so there are no individual scores.

25.   Participants take on guises of vampires, werewolves and other creatures of the night.

26.   Participants must take their own water and camping equipment.

27.   She would not have qualified if her sugar pill had been tamoxifen, because participants cannot have taken either drug previously.

28.   The average Branson show runs two hours, and bus tour participants often take in three or four shows a day.

29.   The participants took combination drug therapy for eight weeks and stopped for two weeks to test the concept, known as structured treatment interruption.

30.   The participants took pains to emphasize their unity, but there were many fissures.