His sister likes _____________ the swings.
A. playing on
B. plays on
C. playing at
答案:A
建筑倒塌事故特点主要有()。
A、突发性强、人员伤亡大
B、破坏性强,经济损失大
C、易引发次生灾害
D、救援时间长,危险性大
E、善后任务重,社会影响大
错拉隔离开关应如何处理?