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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。
- retinal polarity 视网膜极性(现象)
- The optical system of the eye stimulate cell of the retina. 眼睛的视觉系统刺激视网膜内的细胞。
- Are there any animals in the polar circles? 南极圈和北极圈内有动物存在吗？
- Sight is made possible by rays of light impinging on the retina. 由于光线射到视网膜上,眼睛才看得见。
- 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
- 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 optical system of the eye stimulates cells of the retina. 眼睛的视觉系统刺激视网膜内的细胞。
- The polar region is the habitat of the polar bear. 北极地带为北极熊的栖息地。
- Note the polarity of the voltage drop across R. 注意R上电压降的极性。
- 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。
- 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。
- Rhegmatogenous retinal detachment in children. 儿童孔源性视网膜脱离。
- A detached retina is more serious. 视网膜剥离就更严重了。
- Love and hatred are polar feelings. 爱与恨是完全相反的感情。
- Rays light impinge upon the retina. 光线射到网膜上。
- Stage 2B: Operculated, traction to retina released. 有盖的，（玻璃体）对网膜的牵引解除。
- He was operated on for detachment of the retina. 他作了视网膜剥离手术。
