backwater trap

例句：

1. 1. The backwater trap is a place where fish can't swim because of the stagnant water.
   滞流池是一个地方，因为静止的水，鱼不能游。
2. 2.The backwater trap is a common problem in urban areas where there are no natural bodies of water.
   滞流池是城市地区常见的问题，因为没有自然水体。
3. 3. The backwater trap is often used to describe situations where progress is slow or unproductive.
   滞流池通常用来描述进展缓慢或不生产的情况。