be doubtful about

基本解释

I would certainly be doubtful about working with a chief financial officer who had an MBA instead of an accounting qualification: give me an FCA or CPA any time.
如果一位首席财务官持有MBA学位，而不是会计资格证书，我肯定会感到怀疑：流转成本会计（FCA）或注册会计师（CPA）要靠谱得多。
The details of his messages are not known, but Mr Eikenberry is said to be doubtful about Mr Karzai’s reliability as a partner and his willingness to curb corruption.
关于艾肯伯里先生具体意见是什么，还无法得知，但是据说艾肯伯里先生怀疑卡尔扎伊总统作为美国合作伙伴及其制止腐败的意愿的可靠性。
However, I don't know whether there will be a blue sky occasionally. Will the dusty storm be more frequently?It is doubtful that the earthquake will come about more often.
但是，不知道天还会不会像现在一样，偶尔会变蓝，会不会风沙更频繁，会不会地震更爱光临。

One clear danger is that they may alienate customers, who will welcome better service but may be more doubtful about uses of the technology such as finely segmenting the market or targeting customers individually.
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President-elect BARACK OBAMA: It's the answer that led those who've been told for so long by so many to be cynical and fearful and doubtful about what we can achieve to put their hands on the arc of history and bend it once more toward the hope of a better day.
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When I talked recently (via email) with ex-BMW chief designer Chris Bangle he was doubtful about driverless vehicles simply because the liability issues it created needed to be resolved before the cars could go on sale.
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