（1）How often does the man help with the art fair？
A.Every week.
B.Every month.
C.Every other month.
（2）What is the man trying to do to help with the problem of water pollution？
A.Clean the river up.
B.Put up some notices.
C.Write to the government.
（3）What has gotten smaller because of the pollution？
A.The number of insects.
B.The number of trees.
C.The amount of grass.