--I am sure Mary will win the first place in the coming competition.
--I think so. She ________ for it for months.
| A．has prepared | B．has been preparing |
| C．had prepared | D．prepared |
One-third of the country ________ covered with trees and the majority of the citizens ________ black people.
| A．is; are | B．is; is |
| C．are; are | D．are; is |
It is no good always complaining about life. ________ ，we are living.
| A．At least | B．Or else |
| C．What's more | D．Instead |
By the time he was twelve, Edison __________ to make a living by himself.
| A．would begin | B．has begun |
| C．had begun | D．was begun |
As its name indicates, the “American Host Family” program gets American families __________in foreign students' lives in America and offers homes for them.
| A．to involve | B．involving |
| C．involved | D．having involved |
A lot of tall buildings __________ in Shanghai in the past three years.
| A．have set up | B．have been set up |
| C．set up | D．were being set up |