Simple past tense and past participle of extemporise.(verb)
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Use "extemporised" in a sentence
"I started to raise my death-chant again -- a purely extemporised farrago of a drug-crazed youth."
"By the time of the duo's extemporised hymn to Edinburgh, which does nothing other than find half-rhymes for words like "hops" and "Five Pound Fringe", this viewer was getting doggerel-tired."
"“I hear and obey,” replied the poet and in an eye-twinkling extemporised these couplets,"