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I am not by any means a poetry expert, but I know a bit about grammar and writing. Ergo, I can say that in Dylan Thomas’s most famous poem, Do not go gentle into that good night, the refrain that the poem takes its name from is ungrammatical. The grammatically correct way to write (or say) this would be “Do not go gently into that good night.” What I want to know is as follows:

a) Is there a historical usage of “gentle” as an adverb and b) if there isn’t, why did Thomas determine that it was okay to use an adjective adverbially? Or is there some poetry-grammar exception that I am unaware of?

marked as duplicate by user067531, Mitch, JonMark Perry, JEL, J. Taylor Aug 23 '18 at 21:01

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  • Comments are not for extended discussion; this conversation has been moved to chat. – tchrist Aug 15 '18 at 18:00
  • Also, this is poetry where anything goes in order to fit the meter. – Mitch Aug 21 '18 at 13:57

The use of gentle as an adverb as well as and other possible non-standard usage of grammar in poetry are referred to as “poetic licence”. As Collins Dictionary notes:

If someone such as a writer or film director uses poetic licence, they break the usual rules of language or style, or they change the facts, in order to create a particular effect.