( ) 1. How many jobs are there in an ecosystem?
A. Five. B. Four. C. Three. D. Two.
( ) 2. What can we know from Paragraph 3?
A. People plant many trees in forests every year.
B. It's difficult for giraffes to find food nowadays.
C. Terrible earthquakes can change ecosystems.
D. Ecosystems only come in a back garden or a big sea.
( ) 3. What does the writer want to tell us in this passage?
A. To ask people to protect the ecosystems.
B. To introduce different jobs in the forests.
C. To teach us how to keep ecosystems balanced.
D. To show the writer's ideas of protecting animals.