1. The larvicide effectively controls the population of mosquito larvae in the area.
这种杀虫剂有效地控制了该地区蚊虫幼虫的数量。

2. The local government is spraying larvicide in stagnant water to prevent the spread of mosquito-borne diseases.
地方政府正在在停滞水体中喷洒杀虫剂，以防止蚊虫传播的疾病扩散。