问题
选择题
The workers demanded that their employer_____ their working conditions.
A．had improved
B．would improve
C．improve
D．will improve
答案
答案：C
题目分析：考查虚拟语气：句意：工人们要求他们的老板改善工作条件。主句的谓语是demand，谓语动词用虚拟语气，用should do，should可以省略，选C。