题目

阅读下面短文,按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空。I went to visit an old friend of mine one 【1】 (sun)afternoon last week. I sat in the car,【2】followed long lines of cars. Finally, all cars started moving 【3】 one stayed still.When I also drove forward, a man was standing outside the car and talking to each driver as they 【4】 (drive)past. With his request refused by these drivers, he kept 【5】 (ask). As I moved on, he also stopped me and asked whether I would do him某溶液只含下表离子中的几种，且各离子的物质的景浓度相等（不考虑水的电离与离子水解）。阳离子K+、NH4+、Fe2+、Mg2+、Cu2+阴离子OH -、CI-、CO32-、SO42 -某同学进行了如下实验（必要时可加热）：下列说法正确的是A. 由沉淀A推断原溶液中一定含有SO42- B. 原溶液中只含有NH4+、Fe2+、Cl-、SO42-C. 泣液A中可能含有K+ D. 沉淀B中一定含有Mg(OH)2