他们天黑时开灯。

They turn the light on at dark.

youdao

天黑时，蝙蝠离开它们的洞穴。

At night, the bats leave their cave.

youdao

当天黑时，我们可能会在没有光的情况下撞到东西。

When it's dark, we may bump into things without the help of light.

youdao

The Evening Star is the, roughly speaking, first heavenly body that's visible in the sky as it gets dark, at least at certain times of the year.

粗略说来,昏星就是,天黑时第一个能看见的天体,至少在一年的某个时间段是这样

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