Je ne suis pas sûr si les noms de ces personnes sont ceux qui possède ces objets mais je vais le considérer comme ça. Dis moi si je me trompe:
To who does this ring belong? It belongs to Meg
Whose umbrella is it? It's Ken's.
Is this cap yours? No, it's the teacher's
Are those scissors hers? No, they're my friend's scissors.
Whose biros are these? The're the Head's biros.
C'est bien cela que tu cherches?