患者24岁,因牙面上横纹就诊,查体:双侧1236牙冠表面见带状凹陷,牙体无色泽改变
可推断致病因素出现时间为
A.1岁
B.3岁
C.5岁
D.7岁
E.9岁
参考答案:A
— Mum, would you please buy me an MP5 player?
— If you can help do the dishes the whole vacation, you ______ have one as a reward.
A.would
B.shall
C.may
D.must
下降需求