'''NUMBEROFARTICLES''' is the number of pages in the main namespace which contain a link and are not a redirect, in other words number of articles, stubs containing a link, and disambiguation pages.
'''CURRENTMONTHNAMEGEN''' is the genitive (possessive) grammatical form of the month name, as used in some languages; '''CURRENTMONTHNAME''' is the nominative (subject) form, as usually seen in English.
In languages where it makes a difference, you can use constructs like <nowiki>{{grammar:case|word}}</nowiki> to convert a word from the nominative case to some other case. For example, <nowiki>{{grammar:genitive|{{CURRENTMONTHNAME}}}}</nowiki> means the same as <nowiki>{{CURRENTMONTHNAMEGEN}}</nowiki>. <!-- Is there a reference for this, other than the source code (for example, phase3/languages/Lnaguage*.php) ? -->