Temporal prepositions are related to time and answer questions like "When?" (point in time) and "For how long?"
Most of these prepositions are used only with a certain case.
Prepositions of Time with Accusative
Rule 1: Here are frequent prepositions of time followed by the accusative case:
1. um: we use it to specify the time
2. bis: indicates that something happens until a certain time
3. für: indicates that something happens within a time span
4. über: indicates that something takes longer than a time span
5. bei: to make a simultaneous process more clear
Prepositions of Time with Dative
Rule 2: Frequent prepositions of time followed by the dative case are:
1. an/am: indicate days of the week and times of the day
2. in/im: indicate future or a period of time
3. vor/nach: indicate a time before or after a certain point in time or event
4. seit: indicates when something started in the past (starting point and time span)
5. bei: indicates when something happens at the same time
6. ab /von...an: indicate when something is starting in the future
Prepositions of Time with Genitive
Rule 3: Here are the prepositions of time followed by the genitive case:
1. während: we use it when two things happen simultaneously
2. innerhalb: indicates that something happens in a certain time period
3. außerhalb: indicates that something happens outside of a certain time period