Possessives and ownership

Two choices, one after the other: the word depends on the owner, the ending depends on the thing owned (gender and case), exactly like ein.

• Like English: sein = his / its, ihr = her / their. The trap is elsewhere: ihr also means "you (plural)" and "(to) her", and Ihr with a capital is the polite "your". Er liebt seine Frau. Sie liebt ihren Mann.
• euer drops its -e- as soon as it takes an ending: eure Wohnung, euren Hund. unser keeps it: unsere Wohnung.
• Mine, yours: used on its own, the possessive takes the endings of dieser: Das ist mein Schlüssel → Das ist meiner. Das ist mein Auto → Das ist meins.
• Ownership: in writing, the genitive (das Auto meines Vaters); in speech, von + dative (das Auto von meinem Vater). With a first name: -s with no apostrophe, placed in front: Annas Auto. After -s, -z, -x: just an apostrophe (Max' Fahrrad).

Er besucht seine Mutter, und sie besucht ihre Mutter.

He visits his mother, and she visits her mother.

Ist das dein Schlüssel? Ja, das ist meiner.

Is that your key? Yes, it's mine.

Das ist Annas Fahrrad.

That's Anna's bike.