It's ....... eraser.
a
an
Is this a book?
No, it isn't. It is a notebook.
Is this a pencil case?
No, it isn't. It is a desk.
What is it?
It's a book.
What is it?
It's a chair
Is this a pen?
Yes, it is.
What is it?
It's a notebook
What is it?
It's an eraser.
What is it?
It's a desk
What is it?
It's a pen.
What is it?
It's a backpack.
What is it?
It's a pencil case.
What is it?
It's a pencil.
What is it?
It's a ruler.