未成年人在遇到社会、学校和家庭保护出现“保护缺位”时，不能等待别人的保护，这就要求我们加强[     ]

A．逆来顺受意识

B．忍气吞声意识

C．退却逃避意识

D．自我保护意识

Professor Li, who I ____ abroad, still teaches in Peking University.

A．think went

B．think to have gone

C．thought went

D．thought had gone