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- A skilled person can split slate into layers. 手巧的人能把板岩剖成片。
- Scientists have studied the migration of fish over long distances. 科学家研究过鱼类远距离回游的现象。
- There are several layers of meaning. 有几层不同的含意。
- The growth of successive layers of a cell wall. 敷着，附着细胞壁连续层的生长
- This layer of rock contains a lot of flint. 这一岩层中有大量燧石。
- Composed of layers bonded together. 层积的由合在一起的薄层组成的
- The inner layer of the wall of a spore. 孢子内壁孢子壁的内层
- There has been a migration of people from the country to the towns. 人们从乡下移居城镇。
- There is a fine layer of dust on the desk. 桌子上有一层薄薄的尘土。
- migration layers 输导层
- They drilled through several layers of rock to reach the oil. 他们钻透了几层岩石以寻找石油。
- The middle, usually fleshy layer of a fruit wall. 中果皮果皮中间通常含肉较多的那一层
- There was a huge migration of people into Europe because of the war. 因为战争，大量的移民涌入欧洲。
- The bottom layer is a mixture of sand and clay. 最下面的一层是沙和泥的混合物。
- Seabirds will fly from here to another place for migration every year. 海鸟每年都要从一个地方迁徙到另一个地方。
- A fine layer of dust covers everything. 所有的东西都盖了一层薄薄的灰尘。
- A layer, as of doubled-over cloth or of paperboard. 一层一层，如折叠过的布料或纸板的
- A surface, layer, or mass of frozen water. 冰面冻结的水的面、层或块
- A thin layer of bone, membrane, or other tissue. 骨骼、粘膜或其它组织的薄层
- By mid-October Operation Migration was ready. 到了10月中旬，迁徙行动的准备工作就绪。
