下列哪项病变最好发于儿童时期脊柱（）
A.骨囊肿
B.动脉瘤样骨囊肿
C.骨嗜酸性肉芽肿
D.软骨黏液样纤维瘤
E.骨巨细胞瘤
参考答案：C
We gave away bulletins door to door to call on people to help others warm-heartedly, only ____to have a drink from time to time.
A．to stop
B．stopping
C．stopped
D．having stopped
拆卸与装配轮毂的技术要求包括（）损坏的轮辋和轮毂螺栓。
A.清洗
B.更换
C.调整
D.修配
