滚动螺旋传动不具有自锁性。( )
参考答案：对
_______ amazing movie Rio2 is! Many people like to watch it.
A．What
B．How an
C．What an
D．How
(1)交通中断 (2)义务劳动(3)紧急动员 (4)山洪爆发(5)恢复交通正确选项为( )
A．1-4-2-3-5
B．2-3-5-4-1
C．4-1-3-2-5
D．3-4-5-1-2
