sorry
1.I am sorry后面往往接but。例如：I'm sorry, but I have an engagement for Sunday afternoon. 和I am sorry, but the matter quite slipped my memory. 某人（假定是David Jackson）为了某种原因不能出席，托人带来一个字条，字条里可以说David Jackson is sorry he couldn't come, but he had to attend to some urgent business。
2.不可说I am sorry, for I have not answered your letter。参见for 10
3.下面两句都不对：
Sorry to say, he failed in the examination.
The boy, sorry to say, fell into the brook.
该改作：
I am sorry to say that he failed in the examination.
I am sorry to say that the boy fell into the brook.
4.不可说it is sorry that...。
5.not sorry往往有“（暗中）感觉高兴”的意思。例如：She was not sorry when this uncomfortable visit came to an end.