During the period of recent terrorist activities, people not to touch and unattended bag.
A. had always been warned
B. were always being warned
C. are always warning
D. always warned
网友回答
A. had always been warned
(答案→)B. were always being warned
C. are always warning
D. always warned
解析：考查固定句型用法。Be alawys doing sth.一直在做某事，表示赞赏或埋怨的感情色彩，此处从unattended bag.排除A，C，依据warn的用法，人们应该被警告，故选B。