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- In drainage of agricultural lands, a filter or gravel envelope is used to prevent the entrance of fine sand and silt into the drains. 在农田排水中常常采用砾石或过滤层来防止粉细砂和泥沙进入排水沟。
- In drainage of agricultural lands, a filter or gravel envelope is used to prevent the entrance of fine sand and silt into the drains 在农田排水中常常采用砾石或过滤层来防止粉细砂和泥沙进入排水沟。
- Have you stuck down the back of the envelope? 信封背面开口处贴牢了吗？
- He steamed the stamp off the envelope. 他用蒸汽把信封上的邮票揭下来。
- My father scratched gravel for Shanghai last night. 我父亲昨晚匆匆忙忙去了上海。
- The road is covered with gravel. 这路用砾石铺成。
- He glued a stamp onto the envelope. 他把邮票贴在信封上。
- We bumped up and down along the gravel path. 我们沿砾石小路颠簸而行。
- As he picked up the envelope, a key dropped out. 他拣起信封时，一把钥匙掉了出来。
- As she picked up the envelope, a key dropped out. 她拾起信封时，一把钥匙掉了出来。
- Put a stamp on the envelope, will you? 在信封上贴张邮票，好吗？
- He stuck a stamp on the envelope. 他在信封上贴上邮票。
- The gravel ingredient of concrete. 石碴组成混凝土的砂料
- She opened the envelope with her fingertips. 她用指尖弄开了信封。
- Layered gravel and charcoal to make a filter. 将砂砾和木炭分层以做成过滤器
- The envelope's seal was torn open. 信封封缄被撕开了。
- The (flap of the) envelope was unstuck. 信封(的封口)没粘住。
- There are several enclosures in the envelope. 信封内装有几份附件。
- The workers mixed the asphalt with sand and gravel together. 工人们把沥青和沙子、石块混合在一起。
- The car bumped on the uneven surface of the gravel road. 汽车在高低不平的砾石路面上颠簸着。
