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来源:雅诚德英语网
To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop.
举个极端的例子,以单一作物为主的农田是如此不稳定,一年的坏天气或单一害虫的入侵可以摧毁整个作物。