Darken it a bit at the bottom.

在底部加深一点。

youdao

If you have too much gray hair, darken it.

如果白发太多，就染黑它。

youdao

We need to darken it again to add more depth.

我们需要再次变暗增加更多的深度。

youdao

While it appears to darken in the sun like Transitions eyeglasses, the trigger is heat not UV exposure.

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Then, when snow or rain wash them onto an ice floe, they darken its surface and thus cause it to melt faster.

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If we see a person first in a good light, it is difficult subsequently to darken that light.

ECONOMIST: Idea