圆锥破碎机偏心轴套外围磨损5mm以上时,则应更换。
参考答案:错
When someone is ill, he _____ she should try to smile at life. [ ]
A. and
B. but
C. or
D. so
()是教师专业发展的前提和基础。
A、自主性
B、开放性
C、创新性