从沈阳经铁路运往俄罗斯的货物，要求以最短运距条件运往目的地，则需经过我国的国境站是（）。

A. A

B. B

C. C

D. D

They got two free tickets to Canada, otherwise they______ able to afford to go.

A．wouldn’t have been

B．mustn’t have been

C．wouldn’t be

D．hadn’t been