Completion of this work will remove the threat of drought and water-logging. 完成了这项工程，将消除旱涝威胁。
In the United States, cycles of rain and drought seven years ago permitted a deadly form of pulmonary hantavirus, carried by mice, to flourish in the Southwest. 在美国，七年一次的旱涝周期循环，使一种由老鼠传播的肺汉滩川病毒在西南部猖獗起来。
