政府在国家经济建设中主要扮演着参与者的角色和______的角色。
A．领导者 B．指挥者C．规范者 D．执行者
参考答案：C
What’s tree about Professor Lawrence().
A.She has found a new job at another university.
B.She has become the head of the graduate school.
C.She will continue to work part-time.
原始平板通常采用（）平板组合进行刮砂。
A.二块
B.三块
C.四块
D.五块
