A:矿泉水
B:纯碱
C:碘盐
D:食醋
You had better learn to _________ different kinds of problems by yourself.
—Alice, why didn’t you come yesterday?
—I ______, but I had an unexpected visitor.
(2015•资阳)甲血管与心房相连,流动脉血,乙血管与心室相连,流静脉血,甲乙两条血管分别是( )