两个数相乘积为负数，那么这两个数为 [ ]
A．异号
B．同号
C．和为正数
D．差为正数
答案：A
已知函数f(x)＝若f(a)＝，则a＝
( )
A．－1
B．
C．－1或
D．1或－
---We've spent too much money recently.
---Well，it isn't surprising. Our friends and relatives ______ around all the time.
A．are coming
B．had come
C．were coming
D．have been coming
