"The costs of invasive species are so high, literally hundreds of billions of dollars a year," Cmar says.

入侵物种的代价非常高，每年差不多需要数千亿美元。

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However, Cmar says that as transportation into the country has become more advanced, more invasive species have come in on boats and planes, thus worsening the problems posed to ecosystems.

随着进入美国的交通工具起来越先进，更多的入侵物种坐着轮船、乘着飞机来了，从而更加恶化了对生态系统造成的问题。

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However, Cmar says that as transportation into the country has become more advanced, more invasive species have come in on boats and planes, thus worsening the problems posed to ecosystems.

随着进入美国的交通工具起来越先进，更多的入侵物种坐着轮船、乘着飞机来了，从而更加恶化了对生态系统造成的问题。

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