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for a long time; at (great) length; lengthily; long-windedly; tediously
(extending) far; (stretching) out; (lying down) at full length
永々と続いた会議がようやく終わりを迎えた。
The meeting that had dragged on endlessly finally came to a close.
彼は永々と自分の功績について語り続けた。
He went on at great length about his own achievements.
永々とお世話になり、心から感謝しております。
I am sincerely grateful for your long and continued support.