I would like to apologize to you again. I promise it will never happen again.

我再次向您道歉，我保证以后不会再出现类似情况了。

youdao

I apologize again for my carelessness, and wish to meet you again soon! Sincerely yours, Li Ming.

再次由于我的粗心向你道歉，希望能很快再见面。真挚的李明。

youdao

Again, you have to respect your time. If you apologize, you are sending the message that you are doing something wrong by saying no, that somehow you don't have a strong right to say no.

还是得珍惜自己的时间，如果你道歉的话，就好像是在为做错一件事而道歉，这样一来你拒绝的理由也就显得不甚充分了。

youdao

Once again, I apologize to you on behalf Of IMF (International Monetary Fund) for failure to pay your funds on time, which according to records in the system had been long overdue.

FORBES: "Are Your truly dead?" The IMF, Watson and Schrodinger's Cat.