Breakdown of Wir reparieren den Motor meiner Maschine.
wir
we
mein
my
reparieren
to repair
der
who, which, that (relative pronoun; die, das)
Questions & Answers about Wir reparieren den Motor meiner Maschine.
Why is it meiner instead of meine?
meiner is in the genitive case, which shows possession. Because Maschine is a feminine noun (die Maschine), the possessive article mein takes the feminine genitive ending -er.
Why is the owner of the engine placed after the engine itself?
In English, we usually use an apostrophe-s before the noun (like in "my machine's engine"). In German, the genitive phrase almost always comes after the thing being owned. The structure is literally "the engine of my machine".
Why doesn't Maschine get an extra -s at the end to show it is in the genitive case?
In the genitive case, only masculine and neuter nouns get an extra -s or -es added to the end. Since Maschine is feminine, the noun itself doesn't change. The possession is shown entirely by the ending on the article meiner.
Why is it den Motor and not der Motor?
Motor is the direct object of the sentence because it is the thing being repaired. Therefore, it needs to be in the accusative case. Since Motor is a masculine noun, its article changes to den.