You are supposed to arrive on time. [ ]
A. should
B. must
C. have to
D. need
答案:A
下列成语中,一定包含有化学变化的是( )
A.铁杵成针
B.蜡炬成灰
C.积土成堆
D.滴水成冰
我国对房地产经纪人员实行职业资格( )制度。
A.考核 B.会审C.鉴定 D.注册