"Flip" is a short, sharp word for a short, sharp action. "Flip-flop" arose in imitation of the action of going quickly back and forth.

他们听上去都是拟声词 flip音节短促尖锐 用以描述快捷疾速的动作.flip-flop的发音模拟快速往复的动作.flap听上去不正象旗帜和船帆在风中拍打的声音吗?

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Users can lock-on to fast moving subjects throughout the frame using 3D tracking to create sharp images of fast action, or use one of the other modes including single point AF, Dynamic AF and Auto-Area AF.

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There is strong and often inventive action, genuinely sharp dialogue, and a real story being told.

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But without decisive action and a sharp focus, you might never get a chance to refuel.

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