INC 指令不影响( )标志。
A．OF
B．CF
C．SF
D．ZF
参考答案：B
When the fire broke out, Mary didn't know ___.
A．what to do
B．what do
C．to do what
D．what thing to do
有减振和导向传力功能的弹性元件是（）
A.螺旋弹簧
B.钢板弹簧
C.油气弹簧
D.扭杆弹簧
