怎样调整注水井注水量？
参考答案：
①根据配注量计算瞬时流量；
②用下流闸门调节，稳定15分钟；
③记录水表读数。
We students should do what we can _____ the environment being polluted. [ ]
A. respond
B. to keep
C. force
D. to stop
