凡能自由通过限界框架而不抵触者，为（）车辆。
参考答案：合格
甲状腺位于
A．甲状软骨上方B．上达舌骨，下至第4气管软骨环C．后方邻近食管D．前方邻近颈阔肌E．上达甲状软骨中部，下至第6气管软骨环
He talked about a hero ______no one had ever heard. [ ]
A. of whom
B. from whom
C. about that
D. who
