半夏具有的功效是( )
A.燥湿化痰,降逆止呕,消痞散结,消肿止痛
B.清热化痰,软坚散结
C.宣肺化痰,清热散结
D.燥湿化痰,解毒散结
E.燥湿化痰,消肿散结
参考答案:A
.He said that he____________ to Canada a few years ago.
A. had been to B. have been to C. went
直齿锥齿轮齿厚的测量方法有测量()和()两种,常采用测量()的方法