For nouns that just add "s" in the plural, use {{noun}} (with "noun", not the name of the page) to make:

Singular
PiRSquared17/n

Plural
PiRSquared17/ns


For other nouns, use {{noun|leaf|leaves}} to make:

Singular
leaf

Plural
leaves


For nouns where the plural is the same as the singular, use {{noun|moose|moose}} to make:

Singular
moose

Plural
moose


For nouns with two different plurals, use {{noun|index|indexes|indices}} to make:

Singular
index

Plural
indexes or indices


For nouns with no plural, use {{noun|steel|none}} to make:

Singular
steel

Plural
none


For nouns with no singular, use {{noun2}} to make:

Singular
none

Plural
PiRSquared17/n