您要查找的是不是：
- The marriage was held to be valid. 这一婚姻关系是有效的。
- The gas bubbled to the surface of the water. 气体变成气泡升上水面。
- The surface of the liquid gradually crusted over. 液体表面渐渐地结了一层皮。
- The ticket is valid for one month. 这票子一个月内有效。
- A breeze ruffled the surface of the lake. 一阵微风吹皱了湖面。
- A credit card is not a valid proof of identity. 银行发的支票保付卡不是有效的身份证明文件。
- A wave broke across the surface of the pool. 一个波浪从池水表面掠过。
- The calm water surface is very much like a mirror. 那平静的水面十分象一面镜子。
- Acid had pitted the surface of the silver. 酸把银器的表面腐蚀了。
- He is honest only on the surface. 他只是表面诚实而已。
- A film of mucus and bacteria on a tooth surface. 齿菌斑牙齿表面一层粘液和细菌的膜
- The hard outer portion or surface area of bread. 面包皮面包的表面区域的硬皮
- Surface mail takes longer than airmail. 普通邮件比航空邮件慢。
- The surface of the lake is quite still. 湖面相当平静。
- It's2 yuan by surface mail and3.6 yuan by air. 寄平信2元，寄航空要3元6角。
- This license is no longer valid. 这张执照不再有效。
- Wheels won't bite on a slippery surface. 车轮打滑。
- The surface must be thoroughly clean. 表面必须彻底弄清洁。
- The cheque is not valid if it were not signed by the finance director. 如果没有主管财务的董事签字支票就无效。
- The surface between the ribs of a ribbed vault. 梁腹，腹板某扇形拱的胁拱之间的平面
