川楝子、槟榔皆具有的功效是( )
A．杀虫行气
B．杀虫利水
C．行气利水
D．行气疏肝
参考答案：A
— Can I tell my best friend about it?
— No, I don't want anyone else to know it. You _____ keep it to yourself. [ ]
A. must
B. need
C. can
D. may
分析动态电路的三要素法只适用于（）电路。
