双层结构，外层为空心，内层为实心的翻译：Two-layer system, outer layer as hollow, inner layer with solid 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

Double-layer structure, the outer layer of hollow, solid inner

Two-layer system, outer layer as hollow, inner layer with solid

The two-course construction, the outer layer is hollow, the inner layer is a solid

正在翻译，请等待...

Two-layer system, outer layer as hollow, inner layer with solid