pre-emergence sprayer

例句：

1. 1.This pre-emergence sprayer is designed to protect crops from pests before they emerge.
   这种预喷药器设计用来在害虫出现之前保护作物。
2. 2. The farmers used this pre-emergence sprayer to control the weeds in their fields.
   农民们使用这种预喷药器来控制他们田地里的杂草。
3. 3.The pre-emergence sprayer was a game-changer for farmers, reducing the need for chemical pesticides.
   这种预喷药器为农民带来了革命性的变化，减少了对化学杀虫剂的需求。