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very; greatly; extremely; exceedingly; highly; quite
今日の暑さは甚だしく、外出を控えました。
It's extremely hot today, isn't it?
彼の会議中の態度は甚だ失礼で、皆驚いた。
His attitude was extremely rude.
この数学の問題は甚だ複雑で、解くのに苦労した。
This problem is extremely complicated.