Simple past tense and past participle of extemporize.(verb)
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Use "extemporized" in a sentence
"He carried it well, the only noticeable effects being a flush in his eyes and a loosening of his tongue to whimsical fancies and extemporized chants."
"At his order, she threw her weight on the end of a quickly extemporized handspike, easing the pressure and listening to her husband's groans, while Malemute Kid attacked the tree with his axe."
"Bella's ancestry and adding to it an extemporized welcome back to"