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- Radioactive elements are at the normal background level, causing no deleterious pollution. 环境辐射在正常范围之内，不存在任何人为造成的放射性污染。
- Radioactive elements are at the normal background level,causing no deleterious pollution. 环境辐射在正常范围之内，不存在任何人为造成的放射性污染。
- The distance at which the magnetic field from the line becomes indistinguishable from typical background levels differs for different types of lines. 要使输电线产生的电磁场辐射等级和典型的背景电磁辐射等级差不多，这个距离得随输电线的不同而变化。
- A Study on the Selenium Background Level in the Soils in Guizhou 贵州省土壤硒的背景值研究
- He has a strong political background. 他有强大的政治背景。
- That incessant background music gets on my nerves. 那没完没了的背景音乐令我非常烦恼！
- I'd like a room on the upper level. 我想要楼上的房间。
- We need a mechanical digger to level the ground. 我们需要一台挖掘机来平整土地。
- He has a working-class background. 他是工人阶级出身。
- Get the fall in the background, will you? 把瀑布拍进背景中去好吗？
- I hope you'll be on the level with me. 我希望你对我坦率布公。
- She needs to win this point to level the score. 她要赢得这一分才能将比分扳平。
- A background accompaniment, as for a performer. 伴奏为一个演奏者配音伴奏
- Keep a level head and phone the Fire Department. 保持冷静，打电话给消防署。
- A football field should be level. 足球场地应该平坦。
- She came from a privileged background. 她出身於特权阶层。
- The rising level of crime is a sign of the times. 犯罪率增高是这一时代的特徵。
- He came from an impoverished background. 他出身贫寒。
- This book gives the background of the Civil War. 这本书叙述了南北战争的背景。
- I have told the whole story on the level. 我已经诚实地把整个事情经过讲出来了。
