The kick is a simultaneous thrust of the legs called a "frog" or breaststroke kick. No flutter or dolphin kicking is allowed.

蹬腿就是两条腿同时蹬出，称之为“蛙”式腿或蛙泳腿，蹬腿时采用交替式打水或海豚式都是不允许的。

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One frog, one mouth, two eyes, four legs.

一只青蛙，一张嘴，两只眼睛，四条腿。

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That electricity from a Leyden jar or an electric machine would cause the legs of a dead frog to move.

莱顿瓶或电器发出来的电竟使死蛙的腿动起来。

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Quail, frog-legs, shots of frothy foie gras and buttery shallots served out of bowl-sized ivory shells very Birth of Venus made a lasting impression.

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Applying an electric current and getting a muscle to jump is easy. (Alessandro Volta jolted a frog's legs 218 years ago.) Peckham is harvesting the body's own electrical signals to control muscles that have been cut off from the nervous system, a process called functional electrical stimulation, or FES. Peckham runs a group called the Cleveland FES Center, a collaboration among Case Western Reserve and two Cleveland hospitals.

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