Cases are a grammatical tool to express relations of entities to the actions of the sentence. They can be marked by endings, prefixes or through modifications of the word itself.
Many languages have cases, but there are also many that don’t have any cases. Those then use prepositions to express these relations.
German has four cases that mainly revolve around “roles”. Other languages have several cases that are about location in some way. English has cases, too, but they’re pretty “washed out” so you need to know where to look for them.





