1) auction
sculpture
collector
painting
exhibition
art movement

2) These paintings are bought by collectors.
Graffiti is painted in unusual places by some people.
These sculptures aren't made in Europe.
Banksy's work are enjoyed by a lot of people.
The gallery is visited by thousands of students every year.
Graffiti art isn't accepted by some critics.

3) unusual
adore
everyday
influential
intelligent
objective

4) were stolen
was built
were broken
was cleaned
weren't painted
wasn't found