配管通过伸缩缝或沉降缝时,应设()装置。
A.接地
B.跨接
C.补偿
D.防雷
参考答案:C
Mother was satisfied to see her son well _____ for the coming examinations.
A.prepare
B.prepared
C.preparing
D.to prepare
蓼大青叶药材的主要化学成分是()
A.蒽醌类
B.挥发油类
C.黄酮类
D.靛蓝和靛玉红
E.皂苷类