Use 'extemporize' when someone speaks publicly without notes or preparation. The CEO had to extemporize his address when his notes were misplaced.
Pro Tip 2/3
Creative Challenge
'Extemporize' often highlights a person's ability to think and create spontaneously. She had to extemporize dinner with the few ingredients left in the fridge.
Pro Tip 3/3
Pressure Response
'Extemporize' is used when an unexpected situation forces an immediate reaction. Stuck in the elevator, he had to extemporize a way to calm the others.