insecticidal activity

例句：

1. 1.The insecticidal spray is effectiveagainst mosquitoes.
   这种杀虫喷雾对蚊子有效。
2. 2. The farmers use insecticidalsoap to kill the larvae ofaphids.
   农民使用杀虫肥皂来杀死蚜虫的幼虫。
3. 3. The insecticidal agent is designed to killinsects without harming beneficial organisms.
   这种杀虫剂设计用来杀死昆虫，而不伤害有益生物。