In Indo-European languages, first-, second-, and third-person pronouns are typically also marked for singular and plural forms, and sometimes dual form as well (grammatical number). Some languages, especially European ones, distinguish degrees of formality and informality (T-V distinction).
Some other languages use different classifying systems, especially in the plural pronouns. One frequently found difference not present in most Indo-European languages is a contrast between inclusive and exclusive "we": a distinction of first-person plural pronouns between including or excluding the addressee.
Some other languages have much more elaborate systems of formality that go well beyond the T-V distinction, and use many different pronouns and verb forms that express the speaker's relationship with the people they are addressing. Many Malayo-Polynesian languages, such as Javanese and Balinese, are well known for their complex systems of honorifics; Japanese and Korean also have similar systems to a lesser extent.
Other verbs in English take the suffix -s to mark the present tense third person singular.
In many languages, such as French, the verb in any given tense takes a different suffix for any of the various combinations of person and number of the subject.
The grammars of some languages divide the semantic space into more than three persons. The extra categories may be termed fourth person, fifth person, etc. Such terms are not absolute but can refer depending on context to any of several phenomena.