1.   He knows a joke when he hears one.

2.   He knows the joke that the sandbar is the newest international bridge into Mexico.

3.   I only know so many jokes.

4.   I know the jokes.

5.   Jordan is first seen giving up basketball to try baseball, and the film makes knowing jokes about this switch.

6.   Some dealers who know Saatchi joke that he might well have paid the nude protesters who marched on the gallery in support of the show.

7.   We know the joke but laugh anyway.