If you’re in Florence, Italy and see a man on a ladder ________ the dust off statues and buildings, don’t worry. It’s just Alessandro Ricci ________ material for his famous smog painting.

Don’t leave the water ________ while you brush your teeth.　

         from the moon, our earth, with water          seven percent of its surface, appears as a “blue ball”.

I was chatting on the Internet last night when I smelt something   in the next room．

The man with a scar across his face is said _________ many valuable items from the museum.