他们清理了这条河，这是为期一周的环保营的一部分。

They cleaned up the river as part of a week-long environmental camp.

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在2007年，NASA的科学家联合俄罗斯科学家乘船考察了这条河的变迁(为时三周)，以及这种类型的生态系统可能如何被气候变化所影响。

In 2007, NASA scientists joined Russian scientists to travel down the river by boat for three weeks to study the transition and how these types of ecosystems may be affected by climate change.

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但是阅读却可以帮助到每一个人。因此，雅可布和他的同事们在受灾地区分发传单。在过去的两周里，他的团队致力于米索里河的洪水。

But reading is something that can help everyone.So Jacobs and his colleagues distribute fliers in disaster areas.In the past two weeks, his team has focused on the Missouri River flooding.

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