be doubtful about

基本解釋

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.
如果一位首席財務官持有MBA學位，而不是會計資格證書，我肯定會感到懷疑：流轉(zhuǎn)成本會計（FCA）或注冊會計師（CPA）要靠譜得多。
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.
關(guān)于艾肯伯里先生具體意見是什么，還無法得知，但是據(jù)說艾肯伯里先生懷疑卡爾扎伊總統(tǒng)作為美國合作伙伴及其制止腐敗的意愿的可靠性。
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，不知道天還會不會像現(xiàn)在一樣，偶爾會變藍，會不會風沙更頻繁，會不會地震更愛光臨。

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.
ECONOMIST: Always-on people
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.
NPR: Obama Must Manage Great Expectations
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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