It is regrettable that the police were not informed sooner.

遗憾的是没有早些报警。

《牛津词典》

We do not know why this error has occurred, but it is regrettable that the claimed drastic reduction in the extent of ice in Greenland has created headline news around the world.

我们不知道为什么这个错误会发生，但是，令人遗憾地是，格陵兰岛延伸的冰大幅减少的宣称已经导致了世界各地的头条新闻。

youdao

In this world, it is exactly the lack of wisdom that causes many regrettable things to happen. Therefore, wisdom is supremely precious, either in a worldly sense or spiritually.

世间很多令人后悔之事的发生，都是因为缺乏智慧的缘故，可见不论是世间还是出世间，智慧都是无比珍贵的。

youdao

And it is regrettable that the leadership in Pyongyang chose to take this course in flagrant violation of its international obligations.

WHITEHOUSE: Press Briefing by Press Secretary Jay Carney,

It is regrettable that the bully pulpit works just as effectively for a president determined to exploit public opinion as one more willing to educate the public.

FORBES: Voters Press Repeat

"It is regrettable that the rest of the consignment was not intercepted but hardly surprising as the police are woefully ill-equipped and often do not even have enough gasoline to operate their vehicles, " he said.

BBC: NEWS | Africa | Deserted cocaine boat in Senegal