任脉起于小腹，止于（）
A.咽喉
B.口唇
C.鼻
D.眶下
E.小腹
参考答案：D
His father thought about ______ to England or Italy, but decided _____ France. [ ]
A. to go, to
B. to go, on
C. going, to
D. going, on
某烃的蒸气对H2的相对密度为39，该烃中碳元素的质量分数为92.3%，氢元素的质量分数为7.7%，则该有机物的分子式为( )
A．C2H2
B．C2H4
C．C6H6
D．C3H6
