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- On Gauge Invariance and Vacuum Polarization 规范不变性与真空极化
- The two systems of government are polar opposites. 这两种政体正好相反。
- Some pumps and all vacuum cleaners work by suction. 有些泵和所有真空吸尘器都是借吸力工作的。
- Most insect do not live in polar region. 大多数的昆虫不在极地地区生存。
- His wife's death left him a vacuum in his life. 他妻子的去世使他的生活变得空虚。
- Her husband's death left a vacuum in her life. 她丈夫的死使她的生活变得空虚。
- Some people are living in a vacuum. 有些人过着与世隔绝的生活。
- A vacuum cleaner is a handy household tool. 吸尘器是一种使用方便的家庭用具。
- The shop repairs vacuum cleaners. 这家店修理吸尘器。
- Are there any animals in the polar circles? 南极圈和北极圈内有动物存在吗？
- The porter turned off the vacuum. 清洁工关掉真空吸尘器。
- The symbol for the speed of light in a vacuum. 表示真空中光速的物理符号
- Located or found in one of the Polar Regions. 环极的，围绕极地的位于或发现于一个极地区域中的
- Sealed under low pressure or a partial vacuum. 抽空密封的在低压或部分真空状态下密封起来的
- In spite of vigilance a polar bear escape from the zoo. 尽管警戒很严，北极熊还是逃出了动物园。
- vacuum polarization 真空极化
- The polar region is the habitat of the polar bear. 北极地带为北极熊的栖息地。
- Dirt and dust are drawn into a vacuum cleaner by suction. 污物和灰尘被吸入吸尘器。
- Although they can swim, the polar bears are terrestrial animals. 北极熊虽然会游泳，但也是陆栖动物。
- We could not pull apart two plates which enclosed a vacuum. 如果两个盘子间是真空，我们就无法将它们分开。
