Sentence:  Dear humanity, we <WSD>regret</WSD> bein' alien bastards, we <WSD>regret</WSD> comin' to Earth, and we most definitely <WSD>regret</WSD> the Corps just blew up our raggedy-ass fleet! 
Meaning of the word marked with <WSD> tags:  To feel sorry about (a thing that has or has not happened), afterthink: to wish that a thing had not happened, that something else had happened instead.