氧化锌避雷器较普通阀型避雷器所不同点，是内部无间隙及有优良的伏安特性。（）
参考答案：对
We were deeply impressed by the schools and teachers________ we had visited there.
A．where
B．which
C．that
D．who
小承气汤方中，大黄的煮法哪项是正确的：
A．与他药同煮
B．后下
C．先煮
D．麻沸汤浸泡
E．以上都不对
