The pipes had frozen and the heat had gone off. We phoned the plumber. He couldn't come for two days. He had been swamped with emergency calls.(compound-complex sentence)
【正确答案】：Because the pipes had frozen and the heat had gone off, we phoned the plumber. But he couldn't come for two days, for he had been swamped with emergency calls.
【题目解析】：p22
