单项选择题
A．its detailed travel information B．its unique booking system C．its longest business flights D．its global service network
A．have been to the four comers of the earth B．travel around the world on business C．want to explore the eight airlines D．need support all along the way
A．feeling pain is part of our life B．pain should be avoided at all costs C．feeling pain can be an interesting thing D．magic power is essential for reducing pain