All the time you are in doubt about the cause of your illness, you are fighting against an invisible enemy.

一直以来你都在怀疑自己的病因，你是在和一个无形的敌人斗争。

《柯林斯英汉双解大词典》

I'm rather in doubt about his explanation of this question.

我对他对这个问题的解释相当怀疑。

youdao

Perhaps you are in doubt about the above.

或许关于上述种种你是存在疑问的。

youdao

Last year,several scientists had expressed doubt about the possibility of the large Himalayan glaciers melting in a few decades.

VOA: standard.2010.01.23

Why should doubt about the veridical or truth-affirming possibilities of interpretation be so widespread in the twentieth century?

对确认为真的解读可能性的怀疑,为什么会在20世纪如此普遍？

耶鲁公开课 - 文学理论导论课程节选

But the crucial thing hasn't yet happened, because after all, in all of these accounts, even that of Hegel, there is no doubt about the authority of consciousness to think what it thinks.

但重要的事情仍未发生，因为毕竟刚刚讲过的所有思想，甚至是黑格尔的，也没有,质疑意识思考所思之物的权威。

耶鲁公开课 - 文学理论导论课程节选

And when in doubt about any of the above, just be sure to trust the lunch gods.

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Common sense should prevail, but if you are in doubt about the appropriateness of a Tweet or posting, discuss it with your editor before sending.

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If in doubt about the blue marks, be sure to double-check with your pediatrician as your son gets older or consider a visit to a dermatologist.

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