根据《电信服务规范》规定，电信业务经营者停止经营某种业务时，应提前（）日通知所涉及用户，并妥善做好用户善后工作。
参考答案：三十
---What made you so_________?
---Oh, Mr Wu told us a funny story and it made us _________.
A．happy, to laugh
B．happily, to laugh
C．happy, laugh
D．happily, laugh
插条造林
