regrettable

1. ADJ You describe something as regrettable when you think that it is bad and that it should not happen or have happened. 不幸的[正式]

The army said it had started an investigation into what it described as a regrettable incident. 军方说已经开始调查这起据称的不幸事件。

2. regrettablyADV 不幸地

Regrettably we could find no sign of the man and the search was terminated. 不幸，我们无法找到这个人的任何踪迹因此搜寻停止了。