無疑;確實;毫無疑問;的確
beyond (any) doubt
無疑;確實
in a way that shows that sth is completely certain
The research showed beyond doubt that smoking contributes to heart disease.這項研究確實表明吸菸會導致心臟病。
without / beyond doubt
毫無疑問;的確
used when you are giving your opinion and emphasizing the point that you are making
This meeting has been, without doubt, one of the most useful we have had so far.這無疑是我們迄今為止最有用的一次會議。
釋義來自《牛津高階英漢雙解詞典》第 9 版