In the graphs below, orange represents informal speech (tu, ты, ni), blue represents formal speech (vous, Вы, vi), and purple represents direct speech.
Direct speech is distinguished here as neither formal nor informal because of variation across the languages. In Russian, direct address, meaning the use of someone's name, can have varying degrees of familiarity depending on what form of the name is used. In the direct speech in our Russian graph, the use of names varies from "Профессор Дамблдор" (very formal) to "Альбус" (informal) in McGonagall's speech. In Swedish, only the professors address each other using their names. In French, there is an almost-even split between formal and direct speech between Dumbledore, McGonagall, and Hagrid.
In the graphs, one can easily make out general trends even from a limited sample. Vernon and Petunia Dursley always use informal speech with each other, as would be expected between husband and wife. Informal speech is much rarer between Dumbledore and McGonagall, only occurring in Russian.
Hagrid's connections are varied across the languages. He almost always uses direct address in his speech as a sign of respect, using Dumbledore and McGonagall's "Professor" titles regularly. In Russian, only Dumbledore addresses him informally, signaling a close relationship. Yet in French, there is more relational distance, as Dumbledore only does not use informal speech at all with Hagrid.
