1.   A female employee is known to associate after work with a sexually active crowd of young people.

2.   A gun is known to fire bullets at precisely three hundred and thirty meters per second.

3.   And they Decided for reasons best known to themselves to invest some of their winnings in buying people like me.

4.   As we now know to our cost, the disease is highly contagious.

5.   At this stage, the rules in use are known to all, and all agree on what the rules are.

6.   But if moderation works, who knows to what heights of political harmony it might lead?

7.   Citizens thus had a legal duty to reveal felonies known to them.

8.   Crawford is best known to television audiences as a lovable idiot.

9.   Diamond is probably the hardest substance known to man.