急性脑血管病在发作24小时内症状可完全消失的是（）
A.短暂脑缺血发作
B.脑血栓形成
C.脑栓塞
D.脑出血
E.蛛网膜下腔出血
参考答案：A
My grandparents _________for fifty years and they are both quite healthy now.
A．marry
B．have been married
C．are married
D．have gotten married
结合你的生活经验对代数ab给出具体解释______．
