A.pick them up | B.pick it up | C.pick up them |
A.to clean | B.clean | C.cleaning | D.cleans |
A.makes; did | B.made; does | C.made; did |
A.Is our city clean? |
B.What can we do then? |
C.What makes the air dirty? |
D.What’s the matter? |
E.Where is it from? |
F.What can you see in the sky? |