As noted on their pages, they are inverse properties.
As an example, let’s take a webpage that is part of a website. You could then state one of these:
WebSite
hasPart
WebPage
WebPage
isPartOf
WebSite
It doesn’t matter which one you choose. (But there might of course be consumers that only recognize one of these properties.)
Note: Most of the time, Schema.org doesn’t define an inverse equivalent for a property. For example, there is author
, but no authorOf
. This is because you can use every property for both directions, with the help of the syntax:
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…