German has four cases: nominative, accusative, dative and genitive. They mark grammatical relationships through articles, pronouns and sometimes noun endings. Nominative commonly marks the subject; accusative often marks a direct object; dative appears with certain verbs and prepositions; genitive often expresses possession. Identify the governing verb or preposition before choosing an ending.
A case is a grammatical form that helps show a noun phrase’s relationship to the rest of a sentence. German uses four. Their names sound like a legal department; their everyday jobs are more approachable.
One masculine noun, four forms
Case
Example
What the phrase does
Nominative
Der Mann wartet. — The man is waiting.
Subject of wartet.
Accusative
Ich sehe den Mann. — I see the man.
Direct object of sehe.
Dative
Ich helfe dem Mann. — I help the man.
Object required by helfen.
Genitive
Das ist die Tasche des Mannes. — That is the man’s bag.
Possession relationship.
The man remains the same noun. The sentence asks it to do a different job, so the article changes. In the genitive, this noun also adds -es.
The definite article chart
Case
Masculine
Feminine
Neuter
Plural
Nominative
der
die
das
die
Accusative
den
die
das
die
Dative
dem
der
dem
den
Genitive
des
der
des
der
The chart gives article forms, not every noun ending. Dative plurals commonly add -n when the plural does not already end in -n or -s: mit den Kindern. Some masculine nouns have a separate weak pattern: der Student → den Studenten. Keep those details attached to actual words.
Do not decide from the English translation alone
Helfen takes the dative: Ich helfe der Frau — I help the woman. English puts “the woman” after the verb just as it does in “I see the woman”, but German treats the two verbs differently. Learn helfen + dative and sehen + accusative.
Prepositions also determine case. Mit takes the dative, so mit dem Bus means by bus. Für takes the accusative, so für den Mann means for the man. Neither choice depends on whether the bus or man happens to be moving.
A workable decision sequence
First find the verb and subject. Next check whether the noun phrase follows a preposition; if it does, use that preposition’s pattern. Otherwise check the verb’s object requirements. Finally choose the article using case, gender and number together.
German question words wer, wen, wem, wessen can help once you know the constructions. They are not magic: a beginner who does not yet know whether a sentence calls for wen or wem cannot solve it simply by asking themselves the question.
Practice with reasons
Complete Ich sehe ___ Mann and Ich fahre mit ___ Bus. Answers: den, because sehen takes an accusative object; dem, because mit takes the dative. Learn the reasons with the answers and the chart begins to describe something you can use.