问题补充:
Studies show that people are more to suffer from back problems if they always sit before computer screens for long hours.
A. likely
B. possible
C. probable
D. sure
答案:
(答案→)A. likely
B. possible
C. probable
D. sure
解析: 动词辨析,主语是people,不能和possible,probable连用,排除B,C;be sure to do,表示一定要,务必,不符合句意。所以选A。be likely to do sth.,很可能会怎样。