Ex.2.
2.No,it isn't.It is under the desk.
3.No,they aren't.They are next to the pencil case.
4.No,they aren't.They are under the chair.
5.No,it isn't.It is on the chair.
6.No,they aren't.They are in the bag.
Ex.3.
2.is in the pencil case
3.are under the table
4.is on the table
5.is next to the table