In a prolific manner, or to a prolific extent(adverb)
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Use "prolifically" in a sentence
"The only way to write easily and prolifically is to practise, practise, practise."
"By which I mean "prolifically", although I'm sure many of the documents are excellent."
"He wrote prolifically, intensely, from morning till night, and late at night, except when he broke off to go to the reading-room, draw books from the library, or to call on Ruth."