I am truly sorry to have done…
我对________向你表示道歉。
Please forgive me…
请原谅我曾__________。
I owe you an apology…
我为______向你道歉。
I regret to inform you that I am unable to do..
很遗憾地告诉你，我没法___________。
I am so sorry to have put you through so much trouble…
很抱歉给你带来这么多麻烦，__________。
Invitation
The honor of your presence is requested…
若你能出席________，我（们）将感到万分荣幸。
It”s a pleasure for me to invite you to…
我很荣幸地邀请你参加__________。
We sincerely hope that you make it.
我们真诚地希望你能参加。
We would be honored to have you there with us…
如果您能参加我们的__________，我们将不甚荣幸。
I will cover all the expense involved.
我将负担所有的费用。
Sympathy
I can only imagine how difficult this time must be for you, and I want to extend to you my unwavering support.
我能想象你所经历的一切，而且，我想告诉你，我会永远支持你。