Hello How do you use the genitive case when one or several objects belong to several people? Case 1. John and Mary have a house. That is John and Mary's house. John and Mary have two houses. Both houses belong to both of them. They are John and Mary's houses. Case 2. John and Mary have two toothbrushes. One toothbrush belongs to John and the other belongs to Mary. Are they John's and Mary's toothbrushes? Other examples: John and Mary's children (John and Mary are these children's father and mother) John's and Mary's children (John has his own children whose mother is not Mary and vice versa) Is the above correct? I have two grammars but neither has any reference to this.