19. You recognize your friends and teachers in commercials or other acting gigs.
24. You know these rules for improv are also rules for life.
- The Republican candidates for president will debate Saturday at 9 p.m. ET on CBS for the first time after Donald Trump's runaway win in the New Hampshire primaries.
- MLB issued its first-ever lifetime ban for performance enhancing drugs to New York Mets' Jenrry Mejia.
- And how well do you know what happened in the news this week? Take our quiz.