Apostrophe case

Let's go to the ____________. (Smiths)

Let's go to the . (Smiths)

The ____________ room is upstairs. (children)

___________ sister is twelve years old. (John)

___________ sister is twelve years old. (John)

__________ shoes are on the second floor. (men)

My ____________  car was not expensive. (parents)

_____________ CD player is new. (Charles)

This is the _____________  bike. (boy)

These are the ___________  pencils. (boys)