One-third of the country____ covered with trees and the majority of the citizens______ black people.

In my opinion, mathematics _____fun, but more than 80% of the group _____agree with me. 

Such _________ the difficulties that we are now faced with.

Lucy, together with her classmates,  ________listening to a talk.

The number of students in our school ________about 30,000 and ________them study hard.