is mit a dative preposition
Dative prepositions. Certain prepositions always require their object to be in the dative case. These are known as dative prepositions. Some examples are the prepositions aus, bei, mit, nach, seit, von, auÃer, zu, and gegenÃ¼ber. When you use these prepositions, you must determine which nouns they modify and use dative case markers for those nouns.