丹参
A．主产于河南B．主产于山西、河南、河北C．主产于甘肃D．主产于四川、湖北E．主产于江苏、湖北、河南
参考答案：D
患者男性，因上前牙牙龈反复出现瘘管，X线片显示根管钙化，经过多次正规治疗后无效，拟行根尖手术
该患者适宜采用的手术切口是（）
A.半月形瓣
B.扇形瓣
C.全厚粘骨膜瓣
D.矩形瓣
E.以上皆不正确
(2013·南昌10所省重点中学二模)Mary ________ as a secretary in this company for twenty years and now she stays at home taking care of her own garden.
A．has served
B．had served
C．is serving
D．served
