野生茶树与栽培种茶树叶片上表皮纹饰有明显的差别,其中,野生茶的气孔(),栽培种茶树的气孔()。
参考答案:小而稀疏,不具表皮毛;大而密,并具表皮毛
Although he has lived with us for years, he_____ us much impression. [ ]
A. hadn't left
B. hadn't been left
C. hasn't been left
D. hasn't left
该病例最可能的诊断()
A.右室流出道狭窄
B.肺动脉瓣狭窄
C.室间隔缺损
D.右室双腔心
E.以上都不是