四大文明古国是指哪四国？
参考答案：
古埃及、古巴比伦、古印度、古中国。
London employers were __________ a shortage of school-leavers, while many graduates were looking for better work opportunities.
A．adding up
B．turning to
C．digging out
D．suffering from
依现行《电信条例》规定，分配电信资源可以采用指配方式，也可以采用( )方式。
A．变卖 B．拍卖C．租赁 D．转让
