[{"Bold_text": "verb (used with object)", "List Items": ["to compose and perform or deliver without previous preparation; extemporize :to improvise an acceptance speech.", "to compose, play, recite, or sing (verse, music, etc.) on the spur of the moment.", "to make, provide, or arrange from whatever materials are readily available:We improvised a dinner from yesterday's leftovers."]}, {"Bold_text": "verb (used without object)", "List Items": ["to compose, utter, execute, or arrange anything extemporaneously:When the actor forgot his lines he had to improvise."]}]