Prepositions express the relationship between words or groups of words. They determine the case of the word or group of words they precede. In other words, they govern grammatical case.

They can govern the accusative, dative and genitive cases, but not the nominative. Most prepositions always govern just one case. But there are also dual prepositions that can be in the dative or the accusative. These are called two-way prepositions.

You are already familiar with the following prepositions that require the accusative when they answer the question "Wohin?" (where to). They refer to a direction.