我真的怀疑以前是否有人说过这两句话。

I truly doubt whether anyone has ever uttered either of these sentences before.

youdao

我对这整个想法持怀疑态度。

I was rather dubious about the whole idea.

《牛津词典》

我怀疑这和我们现在看到的没有什么不同。

I doubt that will have anything different from what we watch now.

youdao

It made me wonder if they were trying to tell that I should retire; it felt like a retirement party.

这让我怀疑,他们是不是在暗示,我应该退休了,感觉那就像是个退休派对

耶鲁公开课 - 金融市场课程节选

Yes, it's 7. So, I don't know if this is true or not, but I wonder if that's where the actual name 7-Up came from.

对，是七，我不知道这是不是真的，但是我怀疑这才是,七喜名字的真正来源。

麻省理工公开课 - 化学原理课程节选

Now, I doubt if there's anybody here who is indifferent between the choices, indifferent with regard to the choice between these two lives.

我怀疑这里不会有人,会对这两种选择无动于衷，大家对这两种生命选择都会有所感触。

耶鲁公开课 - 死亡课程节选