能够使主机或路由器报告差错情况和提供有关异常情况的报告是（）协议的功能。
参考答案：ICMP
–Tom, what’s the matter with you? You look so worn out!
--Nothing serious. I ____ my new house all the day and I am afraid I won’t finish until tomorrow afternoon.
A．have whitewashed
B．am whitewashing
C．have been whitewashing
D．shall be whitewashing
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