异步电动机的转动方向与()的方向相同。
参考答案:旋转磁场
—The company has been performing poorly during the past few years.
—In my view, it needs to _______ its image.
A.hold up
B.take up
C.step up
D.polish up
人的不安全行为与物的不安全状态是造成事故的()原因。
A.直接
B.间接
C.根本
D.深层次