具有祛风湿、通经络的药物有（）
A.豨莶草
B.青风藤
C.臭梧桐
D.川乌
E.海风藤
参考答案：A, B, C, E
He wrote a long letter ___he explained what had happened in the accident.
A．what
B．which
C．where
D．how
混和指的是什么？对混和的要求是什么？
