题目

用石墨作电极，电解lmol/L下列物质的溶液，溶液的PH保持不变的是（  ）A．HCl         B．NaOH             C．Na2SO4           D．NaCl  答案：C解析: 短文改错假定英语课上老师要求同学之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，要求你在错误的地方增加、删除或修改某个单词。增加：在缺词处加一个漏词符号（/\），并在该句下面写出该加的词。删除：把多余的词用斜线（\）划掉。修改：在错的词下划一横线，并在该词下面写出修改后的词。注意：1. 每处错误及其修改均仅限一词；2. 只允许修改10处，多者（从第11处起）不计分。When I first learn to write in English, I ran into much difficulties. The main problem was that I always thought in Chinese and tried to translate everything that I came across it while I was reading into my own language. My teacher advised myself to keep a diary. I followed his advices and put down 100 words or so each day.Soon I began to enjoy talk to myself as I was learning to express myself with simple English. One day I wrote a story and showed to my teacher. He liked it very much that he read it to the class. All said that the story was a good one. Their words were an great encouragement to me.