{{contrast}} is a hatnote for categories.
{{contrast |antonym category (|second antonym category)}}
i.e. the category contrasted is taken to be {{PAGENAME}} (the name of the page on which {{contrast}} is transcluded).
{{contrast|X|Y}} produces: To change the copula from "is" to "are", include|copula=are
or |plural=true
(or "on
", "yes
", etc).