颅底陷入症
参考答案：
颅底陷入症：枕骨大孔区结构陷入颅内，枢椎齿状突高于正常水平→枕骨大孔前后径缩短，后颅凹容积缩小→延髓受压、局部神经受牵拉。
比喻：拟人
A．报纸：课本
B．冰箱：洗衣机
C．金丝猴：香蕉
D．月球：月亮
His () behavior made everyone nervous. He was always rushing to open doors and perform other small tasks, apologizing unnecessarily for any inconvenience that he might have caused.
A. oblivious
B. observant
C. obsequious
D. obsolescent
