后阶段的英文：
downstream

downstream是什么意思：
adv. 顺流而下；向（或在）下游方向
adj. 顺流而下的；向（或在）下游方向的

The logs are drifted downstream to the mill.
原木顺流漂到木材加工厂。

We had drifted downstream.
我们漂向了下游。

Communities downstream have been alerted.
下游的社区已经接到了预警。

No downstream shutoff valves are allowed.
不允许有下游关闭阀。

Small steam gash a lanes, to the downstream.
小火轮划开一条水线，向下游驶去。