It is going to be dark soon.

天快要黑了。

《新英汉大辞典》

A leatherback may be able to pick up some body heat by basking at the surface; its dark, almost black body color may help it to absorb solar radiation.

棱皮龟可以通过在水面上晒太阳来为身体获取热量；深色近乎黑色的身体颜色可以帮助它吸收太阳辐射。

youdao

Thinking it might be a thief, she jumped out of bed, opened the door and crept towards a dark shadow.

她想着可能是小偷，就从床上跳起来，打开门，向一个黑影爬去。

youdao

It would be dark by then.

VOA: special.2010.05.01

But honestly, the right question is, will it be as dark as itself?

FORBES: Epic British Science Fiction Series 'Blake's 7' May Get a Remake

The music is tranquil, the pacing is whatever I want it to be, I can collect and horde, I can be a thief or assassin (all my killings are assassinations because I am of the Dark Brotherhood be it contract or not).

FORBES: Why Do Gamers Play One Game for Hundreds, Even Thousands of Hours?

That's because as the Earth moves around the Sun, it is moving into a stationary field of dark matter - and for half the year it will be moving against the tide of dark matter - just like driving into the rain.

BBC: Dark Matter: Experiment to shed light on dark particles