"My brother's house is very old."
Translation:मेरे भाई का घर बहुत पुराना है।
Why isn't it meraa bhaii? Why is it mere? Brother is singular and masculine
Oblique case. Whenever the object is modified (मेरे भाई का घर, where का घर is modifying भाई) then it becomes मेरे.
The corse conductor needs to add a suitable explanation as to why it is "mere bhai" and not "mera bhai"; and why not "mere bhai ke"