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- The two systems of government are polar opposites. 这两种政体正好相反。
- Most insect do not live in polar region. 大多数的昆虫不在极地地区生存。
- Are there any animals in the polar circles? 南极圈和北极圈内有动物存在吗？
- A thin layer of bone, membrane, or other tissue. 骨骼、粘膜或其它组织的薄层
- 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
- membrane polarization 膜极化
- 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。
- The polar region is the habitat of the polar bear. 北极地带为北极熊的栖息地。
- A thin skin or film, such as an organic membrane or a liquid film. 薄皮，薄膜如生物膜或液体膜等细薄的皮或膜
- A tightly stretched sheet or membrane, as on the head of a drum. 绷紧的薄膜状物挤压得很紧的平板或薄膜，如鼓面
- 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。
- A vibrating membrane in the ear helps to convey sounds to the brain. 耳膜的振动帮助声音传送到大脑。
- In spite of vigilance a polar bear escaped from the zoo. 尽管警戒很严，北极熊还是逃出了动物园。
- The polar bear's habitat is the icy waters of the Arctic. 北极熊的栖息地是冰冷的北极海域。
- Love and hatred are polar feelings. 爱与恨是完全相反的感情。
- The membrane of a bat's wing is interdigital. 蝙蝠翅膀的膜是长在趾间的。
- Extending across or crossing either of the Polar Regions. 横越极地任一个横越或穿过两个极地地区中的
- This membrane is semi-permeable. 这层膜是半渗透性的。
- A fold or ridge, as of skin, membrane, or shell. 皱襞如皮肤、膜或壳的褶或隆起物
- A polar bear has a preference for cold weather. 北极熊喜欢寒冷的天气。
