21.   In slalom I know I can win every race if I make no mistakes.

22.   It has long been known in education circles that a clear correlation exists between social class background and examination success.

23.   It was hard to pick out faces he knew in the crowd.

24.   Known in her youth as Conie, she was pert, voluble, intellectually vibrant, adventuresome.

25.   No such distinction was known in the middle ages and it is essentially the creation of later administrators and writers.

26.   Prueher reported that Cohen made his views known in a meeting with Pentagon officials last week.

27.   She works in local radio, and is quite well known in the Houston area.

28.   Somehow I just knew in the end we would get back to the subject of money.

29.   Students are encouraged to learn standard English because this is what they will need to know in the business world.

30.   The brand name has become well known in Britain through clever advertising.