The plant will soon choke ponds and waterways if left unchecked.

如不控制这种植物的生长，池塘和水道很快就要被阻塞。

《牛津词典》

At least in theory, most of the world's governments now accept that climate change, if left unchecked, could become the equivalent of a deadly asteroid.

至少从理论上来看，大部分国家都认同罔顾气候变化将有如遭遇陨石般的致命袭击。

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Fear, if left unchecked, can destroy our lives.

恐惧，如果任其发展，可以破坏我们的生活。

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"This is a heartbreaking example of how the win-at-all-costs culture of sport, if left unchecked, will overtake fair, safe and honest competition, " he said.

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Yet the consequences of unrestricted consumption, which Americans must indirectly bear through the increasingly unbearable burden of Type II diabetes, will become increasingly dire if left unchecked.

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If left unchecked, the problem could lead to failure of the bearing assembly, although related noise and vibration would make this easily detectable by the driver, the company said.

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