We've all had a few head-scratching moments with generics, but far and away the trickiest part of generics is wildcards.

对于泛型我们都经历过一些痛苦的回忆，但毫无疑问通配符是最棘手的部分。

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In a world besotted with gadgetry, few consumer products have generated as much excitement - and head-scratching - as high-definition television.

在这个到处都被小玩意冲昏头脑的世界里，很少有消费品像高清晰电视一样让人激动人心同时又令人哭笑不得。

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It wasn't so long ago that trying to get Linux onto your system hard disk often comprised hours of head-scratching, system resets, and searching the Internet for the right drivers.

不久之前，在您的系统硬盘上安装Linux往往会花上您数小时去苦思冥想、进行系统重启、在因特网上搜索适当的驱动程序。

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"The build was completed with lots of head-scratching and weekend work, " the company said.

BBC: Zipwhip's Textpresso

Also head-scratching: The government is perpetually trying to figure out how to make Social Security long-term solvent.

FORBES: Retirement Caps and Budget Politics

There's a degree of head-scratching going on about why this is the ideal candidate for this particular role.

BBC: The new CG and some raised eyebrows