“零、地分开”应理解为()和()始终分开。
A、零线;中性线N
B、零线;保护线PE
C、中性线N;保护线PE
D、中性线N;相线
参考答案:C
As students, we are supposed to spend more time ______. [ ]
A. study
B. studied
C. studying
D. to study
女,23岁,上前牙两年前不慎折断,未及时处理,现上唇肿胀,检查发现右上中切牙冠折 3/4,叩痛(+++),根管口暴露,探诊(-),牙体变色,前庭沟变浅,并有波动,为缓解疼痛、消除急性炎症,对该病例应及时进行以下应急处理,除了()
A.根管开放引流
B.消炎止痛
C.拔牙引流
D.切开排脓
E.根管冲洗上药