It allows the train to maintain a constant speed through the twists and turns of existing track.

它可以让火车在现有蜿蜒盘旋的轨道上保持匀速。

《柯林斯英汉双解大词典》

And, it moves at a constant speed.

还有，它以一个恒定的速度移动。

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When the locomotive is traveling at a constant speed or idling, the battery rather than the diesel engine can power the motor.

当火车头在相对恒定速度下前进或者空转时，这时电池就为马达提供能量，柴油发动机不工作。

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Substantially more complex than previous aircraft, the new plane required the pilot to attend to the four engines, a retractable landing gear, new wing flaps, electric trim tabs that needed adjustment to maintain control at different airspeeds, and constant-speed propellers whose pitch had to be regulated with hydraulic controls, among other features.

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Making his first Premier League start, Oxlade-Chamberlain was a constant menace to United with his speed and trickery and he set up the home team's equalizing goal in the 71st minute, when his neat reverse pass was swept home by Robin Van Persie, the club's leading scorer.

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When speed of execution is normative and rapid-fire decisions are a constant, the art of reflection can seem quaint, a holdover perhaps from earlier, more sedate times.

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