肝素的禁忌证有：
A．有出血倾向者
B．严重高血压
C．弥散性血管内凝血(DIC)
D．活动性溃疡病
E．孕妇
参考答案：A, B, D, E
下列生活事例中，属于化学变化的是（ ）
A．把西瓜榨成汁
B．铁锅生锈
C．把铁丝弯曲成衣架
D．给自行车瘪胎打气
I can't leave. She told me that I _____ stay here until she comes back. [ ]
A. can
B. must
C. will
D. may
