And, in fact, some algae can be harmful without discoloring the water.

而事实上，有些藻类可以有害却不会使水变色。

youdao

Most of the activity was north of the island, at depths of 16 to 23 kilometers, and on the opposite side from where the plume of volcanic material was discoloring the water.

大部分地震活动在岛的北边约16至23公里深处，和火山喷发物引起海水变色的位置恰恰相反。

youdao

The article of footwear may be treated with discoloring substances, such as dyes or bleaching agents.

鞋类制品可经褪色物质，例如染料或漂白剂处理。

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We can see oil discoloring the ocean, blackening coastlines and covering wildlife, but carbon dioxide is colorless and odorless.

CNN: What if carbon dioxide were as black as oil?

The all-pervasive sea water still left its mark, seeping into the frames and discoloring them with salt stains and algae.

CNN: March 11, 2013 -- Updated 1910 GMT (0310 HKT)

Over the next several months, the erstwhile housepainter whitewashed the brick, discoloring his lime with pigment to give the walls an ancient tint.

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