口字形和环形闷顶火灾，火势呈环形蔓延，必须在火点的下风方向灭火。
参考答案：错
Can you give me a reason to ___________ you absense yesterday?
A．beg for
B．ask for
C．speak for
D．account for
方程0.25x＝1的解是________．
