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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She raised her finger to her lips as a sign for silence.

她举起一根手指放在唇边，示意肃静。

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She raised her finger to her lips as a sign for silence .

她把手指放在唇边示意（大家）安静。

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When you perform certain gestures with your hand--such as touching your thumb to your index finger in the "okay" sign--there are electrical signals associated with that gesture that pass through the nerves in your upper arm as they carry commands from your brain to your hand.

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For example, the Hawaii Sign Language word for father is to wag your finger -- whereas in ASL, it's an open hand with fingers spread and a thumb to the forehead.

CNN: Researchers document distinctive Hawaii Sign Language

The family said these were removed after a few days, but when they next visited there was a nil-by-mouth sign above her bed and they also found faeces under her finger nails.

BBC: Essex