牵引性视网膜脱离可见于（）
A.ROP
B.Eales病
C.糖尿病视网膜病变
D.视网膜中央静脉阻塞
E.眼球破裂伤
参考答案：A, B, C, D, E
Standing on top of the building, ______.
A．the whole city could be seen
B．nothing could be seen
C．we could see the whole city
D．all could be seen
甲买了3枝铅笔和2个作业本，乙买了4枝铅笔和1个作业本，丙买了3枝铅笔和6个作业本，甲比丙少花了4元，乙比甲少花了0.5元，请你算算他们各花了多少元钱？
