机电式（感应系）电能表计度器的第一齿轮与转轴上的蜗杆齿的啮合深度越深越好。
参考答案：错
当钢丝绳严重磨损，其直径小于公称直径的（）时，钢丝绳应立即报废.
A.20％
B.40％
C.13％
D.7％
.This printer is of high quality and very expensive. ________, we would buy __________.
A．Should the price of it be brought down; one
B．If the price of it be brought down; one
C．The price of it was brought down; it
D．Brought down; it
