如果实现了哈罗德的自然增长率，将使( )。
A．社会资源得到充分利用
B．实现均衡增长
C．实现充分就业下的均衡增长
D．经济持续高涨
参考答案：C
光纤直放站没有收发天线隔离度问题，（）可以选择定向或全向天线。
— You shouldn't have talked back to our teacher like that. It was awfully impolite.
— You are right. I _________ crazy at that moment. [ ]
A. could have been
B. can be
C. must have been
D. should have been
