Correct answer:
We know your girl.

Correct answer:
I need your horse.

Correct answer:
That sugar is for our horse.

Correct answers:
That person does not hear your machine.; That person doesn’t hear your machine.

Correct answer:
I know your boy.

Correct answers:
Is she waiting for our boys or for yours?; Is she waiting for our boys or yours?

Correct answer:
Do you know our girl?

Correct answers:
I don’t know their names.; I do not know their names.; I don’t know their name.; I do not know their name.

Correct answer:
The donkey is his.

Correct answers:
We are their kids.; We are their children.