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sincerely; earnestly; wholeheartedly
repeatedly; over and over; again and again
体調を崩さないようくれぐれも無理はしないでね。
Please take care of your health.
くれぐれも遅刻しないでください。
Please make sure not to be late.
くれぐれもお大事にした方がいい。
You should take good care of yourself.