咽的下界是位于（）
A.第4颈椎下缘水平
B.第5颈椎水平
C.第6颈椎上缘水平
D.第6颈椎水平
E.第7颈椎上缘水平
参考答案：D
— The government requires that every primary school student do sports for at least one hour every day.
— _____. It is high time that students took exercise in order to build a strong body.
A．That’s what I don’t agree with
B．That’s not the point
C．No wonder
D．I can’t agree more
阿司匹林红外吸收光谱中主要特征峰的波数是：苯环νC=C（）.
A．3300～2300cm-1
B．1760，1695cm-1
C．1610～1580cm-1
D．1310，1190cm-1
E．750cm-1
