Nominative after 6 verbs:
The accusative ist used:
1. to denote length of time or a point int time
2.
- Das Kind ist vier Jahre alt
3.
10 prepositions are followed by the accusative case if they express movement in a particular direction
an, auf, entlang, hinter, in, neben, über, unter, vor, zwischen
The genitive case is replaced by von in written German:
Free Dative
1. The dative can indicate a person on whose behalf the action is done
The dative case often indicates possession:
- Especially frequent with parts of the body or articles of clothing. The definite article is used rather than a possessive determiner ; the dative usually precedes the item possessed.
If the dative is used rather than a possessive construction (mein or genitive), the person is seen as affected by the action as well.
Regen tropfte ihm auf den Hut.
(he was wearing it and getting wet)
Regen tropfte auf seinen Hut.
(he wasn’t necessarily wearing it)
With some verbs the accusative is an alternative to the dative case to indicate possession of parts of the body:
- if the accusative is used, the whole person is seen as more directly affected.
Nouns and noun phrases after a noun of measurement are most commonly in the same case as the noun of measurement.