Cleaning up the water supply is their top priority.

清洗供水系统是他们的首要任务。

《柯林斯英汉双解大词典》

A few years ago, we started this kind of "favor war" where one of us would do something kind for the other, such as cleaning up the driveway or building a shed, and next time the other would try to top it with another favor.

几年前，我们开始了这种“人情战”，我们中的一个人会为另一个人做一些好事，比如清理车道或搭建棚子，下次另一个人就会试图用另一个人情来顶上。

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She spent all day cleaning the house from top to bottom for our party tonight.

她化了一整天时间把整栋房子彻底打扫干净，就为了今晚的宴会。

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You can use the hot water at the top of the tank for washing and cleaning.

VOA: special.2009.04.20

The various hypothetical scenarios include whether Mr. Blankfein should resign, whether there should be a broader house-cleaning of top Goldman management or whether to separate the chairman and CEO posts now held by Mr. Blankfein.

WSJ: What-Ifs for Goldman Sachs

Victoria Park, owner of Park Pet Supply in Atlanta, says self-cleaning varieties get top billing during this time of the year, particularly for long-haired dogs.

CNN: Pet grooming tools for a less hairy summer

The promise of reducing pesticide use in this country, which uses twice the amount per ton of food as the U.S., is also an emotional issue with the government, which has made cleaning up China's environment a top priority.

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