Are these notebooks?
No, they're not.
Whose shoes are these?
They're his!
What are these?
They're notebooks! / Those are notebooks!
Describe his clothes.
Grey suit, blue tie, brown belt
What's this?
It's a key!
Whose sunglasses are those?
They're hers.
Whose dog is this?
It's theirs!
Describe her clothes.
Black blouse, brown shirt, black pants and white shoes.
What's this?
It's an eraser!
What are these?
Scarf, hat, sunglasses, gloves, belt, tie
Describe her clothes.
White dress, blue jacket, white shoes and sunglasses.
Is this a watch?
No, it's not.