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- keeping river courses clean 河道保洁
- Dredging the river aims at keeping the river course smooth and water clean. 清挖河道是为了保持河道畅通，河水清洁。
- Enclosing river courses for cultivation is prohibited. 禁止围垦河道。
- The groundwater mostly is replenished by river courses. 地下水是由河流提供的。
- The river course is being cleaned. 河道正在被清理着。
- It is prohibited to plant trees or long-stalk crops impeding flood discharge in river courses used for flood discharge. 禁止在行洪河道内种植阻碍行洪的林木和高秆作物。
- Restrict ions of speed should be imposed in river courses where navigation of ships may endanger the safety of embankments. 在船舶航行可能危及堤岸安全的河段，应当限定航速。
- The river course of Yong River in Ningbo is seriously polluted. 甬江宁波段污染较重。
- The bamboo and log rafting in river courses should not affect the safety of flood passage and flood control works. 在河道中流放竹木，不得影响行洪和防洪工程设施的安全。
- River courses without dynamics replenish the groundwater and thus sustain existing Tugai vegetation. 没有河流改道的河流可保持一定的地下水位，而保持已经存在的胡杨林。
- Wipes the teardrops are this river course's star tonight. 拭出的泪珠是今夜这河道上的星星。
- It's important for the college freshman to keep his nose clean. 对大学新生而言洁身自好是很重要的。
- Planting trees or long--stalk crops impeding flood discharge in river courses used for flood discharge. (三)在行洪河道内种植阻碍行洪的林木和高秆作物的。
- The old river course has been filled up and remade into a driveway. 这条河流的故道已经被填平，修成公路了。
- Well, it looks as if they find their way by such landmarks as mountain ranges, coast lines, and river courses. 呃，似乎它们是通过这些界标，如山脉、海岸线和河流水道找到它们的路的。
- Xiaozhou Village is forned by the alluvium of the sea,and so there are many river courses in it. 小洲村是由海水冲积而形成的，所以村内水道纵横。
- Article 24 Local people's governments should in a planned way organize residents to move out of river courses for passage of floodwater. 第二十四条 对居住在行洪河道内的居民，当地人民政府应当有计划地组织外迁。
- For one thing they keep the water clean. 一方面，他们可以保持水的清洁。
- You can keep my book as long as you like. 我的书你要借多久都随你的便。
- Please keep the watch for me while I go swimming. 我去游泳，请代我保管这表。
