网络经济的特征包括（）
A.虚拟化、成本低
B.竞争激烈，合作很难
C.全天候、全球化
D.强大的创新性
参考答案：A, C, D
The old lady likes to keep things in the house, _____ throw them away, though many are useless.
A．more than
B．but also
C．other than
D．rather than
断裂构造如何制约着地下水富集？
