这些薄膜保护植物的内部组织免受外界伤害。

These ___membranes protect the plant's inner tissues from external damage.

这些塑料膜由特殊材料制成，可以有效地阻隔空气。

These plastic ___membranes are made of special material to effectively block air.

细胞膜控制着物质进出细胞。

Cell ___membranes regulate the passage of substances in and out of cells.