“Du” and “Sie” are both translations of “you” and are used to address someone.
If you know a person well and you are in some way familiar with them, or you’re maybe talking to a pet or to god, use “du” to address them.
If you’re writing to them, use “du” or “Du”, both is possible.
“Du” is generally seen as an informal way to address friends, family and people you have a close personal relationship with.
If you’re addressing someone you don’t know well, perhaps a business partner, your teacher, a doctor or any other acquaintance, use the formal “Sie”.
And if you’re not sure whether you should use “Sie” or “du”, use “Sie” to address the person and ask them whether you may use “du”. Please don’t be offended, if they decline your request.
People generally have very different opinions on whether or not they should be addressed with “du” or “Sie”. As a different address can mean a shift in the relationship dynamics of a work or personal relationship, many people tend to carefully consider such a change.
– Examples –
Wie heißt du? (second person singular of “heißen”: [du] heißt)
Wie heißen Sie? (third person plural of “heißen”: [sie] heißen;
Beware: “Sie” can be used to address a single person or several persons)
Wo bist du? (second person singular of “sein”: [du] bist)
Wo sind Sie? (third person plural of “sein”: [sie] sind)
- in den Zoo gehen – going to the zoo
Du gehst in den Zoo? – You’re going to the zoo?
Sie gehen in den Zoo? – You’re going to the zoo?
- zum Arzt gehen – going to the doctor
Du gehst zum Arzt? – You’re going to the doctor?
Sie gehen zum Arzt? – You’re going to the doctor?