What is the syntax and context for declaring a subproperty?

From semantic-mediawiki.org

Can you give an example that shows the differences between a property declaration and a subproperty declaration?

Pjrich 21:32, 3 November 2011 (CET)

14:43, 10 February 2014

There is no difference when it comes to declaring the values of a property on a particular page, if that's what you mean.

23:25, 23 February 2014