12. The living standards of people in remote areas _________.
A. will be risen B. will arise C. will raise D. will be raised
13. They didn’t stop __________ until 11.30 pm when there was a power cut.
A. to sing and dancing B. singing and dance
C. singing and dancing D. to sing and dance
14. Yuri Gagarin was in orbit in a spaceship _______ moved around the Earth at the speed of more than 17,000 miles per hour.
A. which B. at which C. it D. this
15. Drinking enough water is a vital part __________ it keeps your body functioning properly.
A. because B. or C. but D. although