连接体熔模要求位于接近切端或牙合方1／2 ，其面积不应小于
A. 4mm²
B. 5mm²
C. 6mm²
D. 7mm²
E. 8mm²
查看答案
连接体四周外形设计应
A. 圆钝，不能形成狭缝
B. 可形成V形结构
C. 邻间隙可不预留空间
D. 不必考虑强度、自洁性和美观性
51. Which of the following situations is most dangerous according to the passage?
Adults giving a lift to teenagers on the highway after 10 pm.
B. A teenager driving after midnight with passengers in the car.
C. Adults driving with three or more teenage passengers late at night.
D. A teenager getting a lift from a stranger on the highway at midnight.
52. According to Paragraph 3, which of the following statements is true?
A. Teenagers should spend more time learning to drive.
B. Driving is a skill too complicated for teenagers to learn.
C. Restrictions should be imposed on teenagers applying to take driving lessons.
D. The licensing authorities are partly responsible for teenagers' driving accidents.
53.A suggested measure to be taken to reduce teenagers' driving accidents is that.
A. driving in the presence of an adult should be made a rule
B. they should be prohibited from taking on passengers
C. they should not be allowed to drive after 10 pm
D. the licensing system should be improved
微信支付 
支付宝支付