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very; very much; greatly; considerably; highly; exceedingly; a great deal; a lot; to one's heart's content
この計画に大いに期待している。
I have great expectations for this plan.
大いに議論が盛り上がって時間を忘れた。
The discussion became very lively.
彼の成功を大いに喜んでいる。
I'm very happy about his success.