David, turn off the TV _____ no one is watching it.—But it _____ off already! The music is from the radio.[ ]

Is this Mr. White’s office, Mary?— Yes, _____.

He spent at least as much time reading as you _______on line yesterday.

Hobo，what are you doing? —I’mas a Monkey King．

The World Expo (世博会) ____________ in Shanghai now.