以下经脉中，经过心的经脉是
A.手太阴经
B.手少阴经
C.手太阳经
D.足太阴经
E.足少阴经
参考答案：B, C, D, E
选择Mg、O、H、S 四种元素中的适当元素，组成符合下列要求的物质，将化学式填在空格中：
（1）能供给呼吸的气体单质 （2）一种金属氧化物
（3）一种难溶的碱 （4）一种可溶的盐
— Could you tell us ______ ? —About two weeks.
A．how often are you going to be away
B．how often we are going to be away
C．how long are we going to be away
D．how long we are going to be away
