doubtless
adverb formal uk/ˈdaʊt.ləs/ us/ˈdaʊt.ləs/
毫无疑问，毋庸置疑，肯定
used to mean that you are certain that something will happen or is true
They will doubtless protest, but there's nothing they can do. 他们肯定会提出抗议，但却也无能为力。
Doubtless you have heard the news already. 你肯定已经得知这个消息。