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for a long time; at (great) length; lengthily; long-windedly; tediously
(extending) far; (stretching) out; (lying down) at full length
長々と話を聞かされてすっかり疲れました。
I was tired from listening to a long talk.
長々とお付き合いいただきありがとうございます。
Thank you for your long companionship.
長々と説明する必要は特にありません。
There's no need to explain at length.