If you make an "OK" sign with your thumb and finger, that is the shape for the letter "f" in American sign language.

如果你用拇指和其他手指做一个 “OK” 的手势，那就是美国手语中字母 “f” 的形状。

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To turn an option on, prefix the corresponding option letter with a minus sign (for example, -f).

要开启选项，则需要在相应的选项字符前加上减号（例如，-f）。

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The recent impressive profit reports from General Motors Corp. and Ford Motor Co. (F, Fortune 500) are a sign that strong pricing might be more critical to financial health than large unit sales.

最近，通用汽车公司（General Motors Corp）和福特汽车公司（Ford Motor Co.）均公布了巨额利润，这表明对于汽车厂商的财务健康来说，强有力的定价要比巨大的销量更加重要。

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The mid-September drop below the support from the early 2011 highs, line f, was a sign of weakness.

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The DPP will try to convince voters that America's rejection of any sale of new F-16s is a sign that Mr Ma's efforts to strengthen ties with America (as well as with China) have not worked.

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