たいへんお手数をおかけしまして申し訳ございません。
tbd
I'm sorry I have troubled you so much.
I'm sorry to have caused you so much trouble.
I am sorry that I have troubled you so much.
I'm sorry that I have troubled you so much.
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大変， 大へん， たいへん
1. very, greatly, terribly, awfully
2. immense, enormous, great
3. serious, grave, dreadful, terrible
4. difficult, hard, challenging
5. major incident, disaster
非常、极其、非常严重、极其糟糕；巨大、庞大；严重、严峻、可怕、糟糕；困难的、艰难的、具有挑战性的；重大事件、灾难
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申し訳ございません， 申しわけございません， もうしわけございません
1. I'm sorry, (it's) inexcusable
2. thank you very much (for help, etc.)
tbd