工业上常用的碱法生产氧化铝的方法（）。
A、拜耳法
B、串联法
C、烧结法
D、联合法
参考答案：A, C, D
It’s really you to drive so fast on such a rainy day. Slow down!
A．crazy for
B．crazy of
C．wise for
D．wise of
Which of the following is NOT true about unwanted e-mail
A．It costs money to receive them.
B．It's free to store them.
C．It takes time to access them.
D．It takes time to throw them away.
