So, the action of extending the leg backward creates a forward and upward movement (the flight phase).

因此，腿向后伸展的作用力，产生一个向前向上的运动(腾空阶段)。

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The flight phase: As an athlete moves through the air, his leg swings backward and then moves rapidly forward.

腾空阶段：当运动员在空中移动之时，他的腿先向后摆动，然后迅速向前移动。

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The five-segment booster is intended to power the early flight phase of Nasa's proposed Ares 1 launch vehicle - its replacement for the space shuttle.

BBC: Test ignition for 'Moon rocket'

Paul Babakitis, a retired New York City police sergeant who helped restrain the captain, told Fox News Tuesday that he and the attendants worked to calm the rest of the passengers during the last phase of the flight.

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The test, in which an Aegis ballistic missile cruiser shot down a target fired from Hawaii, was the first exo-atmospheric kinetic intercept of a ballistic missile in the ascent phase of flight, and the third intercept from an Aegis warship.

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