WHAT______TO THE FOREST OF THE U.S. IN THE LAST 350 YEARS
22. What______to the forest of the U.S. in the last 350 years?
a. is happening
b. is happened
c. has happened
d. was happened
22. What______to the forest of the U.S. in the last 350 years?
a. is happening
b. is happened
c. has happened
d. was happened