人体力学杠杆3种作用原理是（）
A.增加阻力
B.传递动力和保持平衡
C.减慢速度
D.获得速度
E.省力
参考答案：B, D, E
. It is important to know exactly the message ________ and ________.
A．you want to send it to people; that you try to get them to do
B．sent to people; what do they want to do
C．you want to send; which you want people to know
D．you want to send to people; what you are trying to get them to do
配栀子，清热利湿退黄力强，治湿热黄疸效佳的是( )
A．茯苓B．滑石C．茵陈D．厚朴E．藿香
