注册建造师在两个建设项目担任施工单位项目负责人的行为( )。
A.应事先向建设单位明确
B.应向有关部门备案
C.应事先向监理单位明确
D.是不允许的
参考答案:D
My parents ______ born in Shanghai, but I ______ born in Nanjing.[ ]
A. was, was
B. were, was
C. were, were
D. are, am
简述教师职业的角色特点。