Tom suddenly slipped on a stone. He fell. His head struck the massive table, (compound- complex sentence)
【正确答案】：Tom suddenly slipped on a stone and hishead struck the massive table as he fell.
【题目解析】：根据以上三个单句的关系，我们将第一句和第二句处理为以and连接的并列结构的主句，把第三句处理为主句as引导的状语从句，表示“当他滑倒时”。