If left unchecked, weeds will flourish.

如果不加遏制，杂草就会疯长。

《柯林斯英汉双解大词典》

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》

If left unchecked, the increasing use of technology in today's business can have an alienating effect on employees.

对科技放任不管，科技就会在当今商界中越来越多得被使用，从而对员工造成异化作用，增加人与人之间的陌生感。

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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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