They noted that the grass can absorb and control the spread of harmful wastewaters, like those from pig farms.

VOA: special.2010.02.09

This is individual services like teaching piano or cutting someone's grass or a hairstylist.

还有个人服务，比如教钢琴,或是帮别人修剪草坪或是作一个发型师。

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And while they eat the grass, they may need guard animals to protect them from animals that would like to eat them.

VOA: special.2010.01.19

Hippopotamuses like to stand in the grass and eat most of the day.

VOA: special.2009.08.19