绘图题：画出自并励方式的励磁系统主接线原理图。
参考答案：
如图E-43所示。
根据图片把短文补充完整，每空一词。
My friend is Tom He is1.______ years old. He goes to school 2._______．He gets
up3.______ every day. He has4.______ and 5.______ at school. In spring, he
6._______. In summer, he swims. In autumn, he 7._______. In winter, he
8.________．He likes 9._______ and 10._______.He doesn't like11.______.
腰椎间盘最常见的突出和退变间隙依次排列为( )
A．L3～4、L5～S1、L4～5
B．L3～4、L4～5、L5～S1
C．L5～S1、L3～4、L4～5
D．L4～5、L5～S1、L3～1
E．L4～5、L3～4、L5～S1
1.______ years old. He goes to school 
2._______．He gets 
3.______ every day. He has
4.______ and 
5.______ at school. In spring, he 
6._______. In summer, he swims. In autumn, he 
7._______. In winter, he 
9._______ and 
10._______.He doesn't like
11.______.