Polite: distinguish informal and polite registers
Various languages have various means to express politeness or respect; some of the means are morphological.
In quite a few languages the polite mode involves changing pronoun, person or number when addressing or talking about a respectable person. In Czech, 2nd person plural is used instead of singular; this involves both the pronoun and the finite verb but not a participle, which remains in singular. In this case, different words are selected but all of them also exist in the informal mode. The change is that morphological plural may now be either semantic singular or plural.
In German, Spanish or Hindi, both number and person are changed (morphological 3rd person is used as semantic 2nd person) and in addition, special pronouns are used that do not appear in the informal register ([de] Sie; [es] usted, ustedes; [hi] आप āpa).
In Japanese, verbs and other words have polite and informal forms but the polite register is not restricted to addressing people.
Inf: informal register
Usage varies but if the language distinguishes levels of politeness, then the informal register is usually meant for communication with family members and close friends.
Examples: [cs] ty jdeš / vy jdete (you go.Sing/Plur); [de] du gehst / ihr geht (you go.Sing/Plur); [es] tú vas / vosotros vais (you go.Sing/Plur); [ja] 行かない ikanai (will not go).
Pol: polite register
Usage varies but if the language distinguishes levels of politeness, then the polite register is usually meant for communication with strangers and people of higher social status than the one of the speaker.
Examples: [cs] vy jdete (you go.Sing/Plur); [de] Sie gehen (you go.Sing/Plur); [es] usted va / ustedes van (you go.Sing/Plur); [ja] 行きません ikimasen (will not go).