在恒牙列中患龋率最高的牙是（）
A．下颌第一磨牙
B．上颌第一磨牙
C．对称性的牙
D．上颌侧切牙
E．全口牙
参考答案：A
______ I know, many thousands of tourists from the Mainland have been to Taiwan. [ ]
A. As soon as
B. As well as
C. As much as
D. As far as
双重阴影
