亚当•斯密对于国际贸易提出了（）
A.绝对优势理论和相对优势理论
B.相对优势理论
C.绝对优势理论
D.公平贸易理论
参考答案：C
We hurried all the way to the airport , only that the flight had been called off because of the foggy weather .
A．being told
B．to be told
C．having told
D．to have been told
纵膈的上界是（）
A.胸廓上口
B.锁骨上缘
C.颈静脉切迹
D.胸骨柄
E.胸骨角
