扬声器的两个接线端可以不分极性任意联接。( )
参考答案：错
He told us whether a meeting was still under discussion.
A．to have
B．having
C．have
D．had
漏出液中的LDH与血清蛋白的比值常
A．＜0.6
B．＞0.5
C．＜0.4
D．＜005
E．＞0.6
