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thank you (for your hard work); I appreciate your efforts
配達の方にご苦労さまと声をかけた。
I thanked the delivery person for their work.
雨の中の作業、ご苦労さまでした。
Thank you for working in the rain.
夜遅くまで残った社員にご苦労さまと言った。
I told the staff who stayed late good work.