单项选择题
A．That’s all right. B．No, of course not. C．Yes, I’d love to. D．Yes, I would.
A．$10. B．$11. C．$13. D．$16.
A．Because traveling by air costs too much money. B．Because traveling by air is uncomfortable. C．She thinks traveling by air is very dangerous. D．She is too old to travel by air.