双层复合膜
This layer of rock contains a lot of flint. 这一岩层中有大量燧石。
The inner layer of the wall of a spore. 孢子内壁孢子壁的内层
There is a fine layer of dust on the desk. 桌子上有一层薄薄的尘土。
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
The bottom layer is a mixture of sand and clay. 最下面的一层是沙和泥的混合物。
A fine layer of dust covers everything. 所有的东西都盖了一层薄薄的灰尘。
