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to gasp; to pant; to breathe hard
to suffer; to struggle
山頂で激しく喘いだ。
I gasped heavily at the summit.
老人が苦しそうに喘いでいる。
The elderly person is breathing painfully.
彼は病気で喘ぐように呼吸していた。
He was breathing like he was gasping due to illness.