我们买了一张双面床垫。

We bought a two-sided mattress.

这块双面镜子非常实用。

This two-sided mirror is very useful.

这是一张双面打印的纸。

This is a two-sided printed paper.

这个双面白板可以用来写字和画画。

This two-sided whiteboard can be used for writing and drawing.

这个问题是有双面性的。

The problem is that there are two-sided.