什么是底床单？What is a fitted sheet?

A flat sheet is, as its name suggests, a flat piece of material that can be used to cover the mattress base or used in the summer and in hotels as a layer on top of your body that covers you whilst you sleep. It's also sometimes referred to as a top sheet (to avoid any more confusion on your bedding journey).

A bed sham is a decorative pillowcase that is used to add some aesthetic variety to the bedroom. Typically, bed shams are used on decorative pillows that are removed from the bed at night. Bed shams may also be called pillow shams.