The new management faces some knotty problems.

新的管理层面临着一些棘手的问题。

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Likewise, if one cannot deal with the things in hand, he or she must fail in the following knotty problems.

同样，如果一个人不能处理手头的事情，他或她一定不能解决后续棘手的难题。

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Under his leadership, many knotty problems were smoothly solved.

在他的领导下，许多伤脑筋的问题都迎刃而解。

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But he did admit there were some "knotty problems" for anyone not connected to the web and so unable to get a full list of the products contaminated with Sudan 1.

BBC: NEWS | Business | How are rogue products tracked down?

Among other things, the company has moved more aggressively into offering combinations of business software and technology services that help companies and governments solve knotty problems, such as catching welfare fraud.

WSJ: Apple Profit Muscles Past IBM

Knotty problems of the same sort arise whenever you add an ethical overlay to what is normally a purely economic decision, like shopping for coffee, paying an electric bill or buying an index fund.

FORBES: When Do-Gooders Invest