By increasing or lessening the hours of darkness in each day, the scientists have been able to turn plant growth off and on like an electric switch.

用增加和减少每天黑暗小时数的方法，科学家已经能够控制植物生长，如同控制一个电器开关。

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At the bottom of the stairs my hand met an electric switch. I turned it, and a great electrolier of twelve red globes flooded the cellar with a red light.

到了最下边一级台阶，我的手碰到一个电源开关，我打开它，一座安了十个红灯泡的大型吊灯架让地下室里一片红色。

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This is the guy you picture pulling down a giant electric switch in a shower of fiery sparks.

你可以把他描述成一位在一阵炽热的火星之中拉下一个巨大的电源闸的家伙。

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