This is the ".form/skos:altLabel" template. It should be called in the following format:

{{.form/skos:altLabel
|hostForm=full pagename of host form
|skosClass=eg Concept, Collection, Scheme
|skosName =eg altLabel
|propName =eg skos:altLabel
|propLabel=eg Alternate names
|placeholder=
|text=
}}

Edit the page to see the template text.