溢流阀振动，可能是（）造成的。
A.滑阀卡死
B.螺母松动
C.压力弹簧变形
D.进出油口反接
E.滑阀配合过紧
参考答案：B, C, E
Is this research centre _____ is full of modern equipment you always mention. [ ]
A. where
B. that
C. the one that
D. the one where
脱氧核苷酸是怎样生成的？
