B2 毫无疑问
used to emphasize your opinion
  She is without (a) doubt the best student I have ever taught. 毫无疑问她是我教过的最优秀的学生。 
 It was, without doubt, the worst restaurant I'd ever eaten in. 
Coming here has been, without a doubt, the most exciting and important experience of my life.
 Without doubt, it is his best book.
 It is, without a doubt, the culinary capital of Europe.
 Without a doubt, the coastal tour was the highlight of our trip to Portland.
 See also: doubt noun