When we extend the complexType, which contains a sequence A with a sequence B, then the sequence B will be appended to sequence A.

We can simulate the same behaviour in Relax NG using the "define" and "ref" elements.

When we extend a complexType, which contains a "choice", with another "choice", then the result will be a sequence of the choices.

We can simulate the same behaviour in Relax NG using the "define" and "ref" elements.