I doubt the feasibility of the plan.

我怀疑这个计划的可行性。

《牛津词典》

"Somebody would have seen her."—"I doubt it, not on Monday."

“有人可能见过她。”—“我不信，不可能在星期一。”

《柯林斯英汉双解大词典》

I agree with it in principle but I doubt if it will happen in practice.

我原则上是同意它的，但我怀疑在实践中它是否会发生。

《柯林斯英汉双解大词典》

"I doubt if you can understand how happy this modernizing has made me.

VOA: special.2009.12.07

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

I doubt it.

我很怀疑

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While the three certainly have the opportunity to retire early, I doubt they will.

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Truth to tell, I doubt that anybody will remember it a year from now.

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But finally, I doubt that even a restricted opening like that that would occur.

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