您要查找的是不是：
- He came to look at the drainage. 他是来检查排水设备的。
- The drainage system has been aged. 排水系统已经老化了。
- drainage manhole 排水用人孔
- The drainage of the town is not good, some of the pipes are broken. 城里的排水系统不好,有些水管断裂了。
- Someone is working in the manhole. 有人在（锅炉的）检修孔中工作。
- I need to find a manhole tool... 我需要找个通道盖子工具...
- Here's the question: Why are manhole covers round? 这个问题是：为什么下水道井盖都是圆的?
- We must dig a drainage ditch to run off the water. 我们得挖一条排水渠把水排掉。
- Or the manhole cover outside your apartment? 还是你公寓外面的下水井盖?
- Why are manhole cover round in shape? 点解下水道的盖是圆形的?
- Please move the manhole cover away. 请将人孔盖移开。
- We can make a manhole for servicing. 可做维修清洗人孔。
- The town's drainage is very efficient. 这城市的排水系统很好。
- Cast iron manhole covers are the best alternatives. 是铸铁井盖最理想的替代品。
- Other areas shall use “B” type manhole covers. 其余的人孔盖为B型人孔盖。
- A drainage passage, as to a culvert. 排水沟排水通道，如阴沟
- Is there adequate drainage where needed? 需要排水的地方其排能是否足够?
- Pancreatic abscess obviously requires drainage. 胰腺脓肿显然需要引流。
- The area has good natural drainage. 这个地区有良好的天然排水系统。
- The bricks were bedded in sand to improve drainage. 沙里埋入砖块，以改进排水系统。
