偶数准则
参考答案：
新老精梳准备工艺都按偶数配置为两道。
It's well known that the earth ______ around the sun. [ ]
A. turned
B. turning
C. turns
D. turn
表达式2! =3的值是 ______。
A．非0值
B．1
C．0
D．2
