糖尿病最具特征的慢性并发症是（）
A.动脉粥样硬化
B.糖尿病足
C.自主神经病变
D.糖尿病视网膜病变
E.直立性低血压
参考答案：D
简述抗日民族统一战线是怎样建立的？
Tom was thinking about how to explain to the teacher why he was late for class, when a good idea _______him.
A．happened
B．brought
C．occurred
D．struck
