Question 54: A survey was _ to study the effects of smoking on young adults.
A. commented B. filled C. conducted D. carried
Question 55: The of the Internet has played an important part in the development of communication.
A. research B. occurrence C. invention D. display
Question 56: When the manager of our company retires, the deputy manager will_____ that position.
A. stand for B. take over C. catch on D. hold on