Things always happen in live theatre. Actors must think quick to cover these malfunctions, seemingly as if they didn’t happen at all. Stage performers always benefit by taking classes in improvisation. Improv will train you to think and act fast when these unforeseen mishaps take place during a live performance. In film, performances do not happen in real time. In the event that an on-screen character drops a line, it’s easy to cut, look at the script and film another take. Nonetheless, one test of film acting is that scenes are frequently shot out of order. An actor may have to cry their eyes out at a funeral in one scene immediately followed by being overly joyous about having just won the lottery.