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to groan; to moan
to roar; to howl; to growl
to hum (engine, wind, etc.); to buzz; to whiz; to sough; to make a low, dull sound
to ooh and aah (in admiration)
to sing in a strong, low voice (esp. traditional chant or recitation)
to be about to burst; to overflow
痛みで患者がうんうんと唸っていた。
The patient was groaning in pain.
犬が低く唸っている。
The dog is growling low.
難しい問題の前で腕を組んで唸るしかなかった。
Faced with the difficult problem, I could only fold my arms and groan.