机动车辆的使用应由专人驾驶和保养,驾驶人员经(),发驾驶许可证,方可驾驶。
参考答案:考试合格
How ______ you say that you really understand the whole story if you have covered only part of the article ?
A.can
B.must
C.need
D.may
深龋检查的重点是()
A.腐质的颜色
B.腐质的硬度
C.龋洞的范围
D.洞底的探痛
E.牙髓的状况