This is more than regrettable; it is dangerous.

　　這不僅僅是令人感到遺憾的，更是危險的。

　　It is regrettable that you should make such a remark.

　　很可惜你竟然說這些話。

　　Yesterday is regrettable, tomorrow still hypothetical.

　　昨天已經逝去，明天還未到來。