X unknown factor (x factor) : find yourself and other people's expertise to find everyone's advantage and it has played out.

X未知因数(X factor)：发现你自己和别人身上的特长，找到每一个人的优点，并将它发挥出来。

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Yet the program still managed to hold its own against CBS' "Survivor" and Fox's "The X-Factor" (in fact, the special edged out Factor in total viewers, see below).

CNN: STORY HIGHLIGHTS

And record-breaking X-Factor superstar Leona Lewis will be releasing the official Sport Relief single.

BBC: Spice Girls launch Sport Relief

The X-factor no one could control, the weather, turned out to be mostly a nonfactor.

WSJ: Social Media