Genitive, and wegen / während

There is a fourth case, and you have been avoiding it successfully for a whole level. The genitive says of — whose thing it is — and it turns up far more in writing than in speech.

Up to now you have said das Auto von meinem Bruder, and that is perfectly good spoken German. This lesson gives you the other way of saying it, mostly so you can read** it.

Two article forms carry almost all of it: des (masculine and neuter) and der (feminine and plural).

Masculine and neuter nouns add -s or -es as well: des Mannes, des Autos, des Urlaubs.

That extra -s is the giveaway. If you see des and a noun ending in -s, you are looking at a genitive — nothing else in German is shaped like that. Feminine and plural nouns add nothing at all.

The possessives take the same endings, which means mein works exactly like ein: meines Bruders, meiner Schwester.

• das Auto meines Bruders

  my brother's car

  masculine → meines + Bruders

• die Wohnung meiner Schwester

  my sister's flat

  feminine → meiner, and the noun does not change

• der Name des Mannes

  the man's name

• das Ende der Woche

  the end of the week

Notice the order. German says das Auto meines Bruders — the thing first, the owner second. English does the opposite with an apostrophe. Expect to want to reverse it, and do not.

Now the genuinely useful half of this lesson: two prepositions that take the genitive and that you will use constantly.

wegen = because of. während = during. Both take the genitive.

• Wegen des Wetters bleiben wir zu Hause.

  Because of the weather we are staying at home.

• Ich konnte nicht kommen, wegen meiner Arbeit.

  I could not come, because of my work.

  feminine → meiner

• Während des Urlaubs habe ich viel gelesen.

  During the holiday I read a lot.

• Während der Woche arbeite ich im Homeoffice.

  During the week I work from home.

Both of these are phrases, not clauses — there is no verb inside them. Compare Ich bleibe zu Hause, weil das Wetter schlecht ist (a clause, verb at the end) with Ich bleibe wegen des Wetters zu Hause* (a phrase). Same meaning, different machinery.

weil + clause with a verb. wegen + noun phrase, no verb.

One honest note about real life. In spoken German you will constantly hear wegen dem Wetter with the dative, and nobody will correct you. It is still considered incorrect in writing, so learn wegen des Wetters first — then you will understand both and be safe in an email.