题目

“苛性钠、烧碱、纯碱、火碱 ”四种俗称中所代表的物质只有 (    ) A． 1种 B． 2种 C． 3种 D． 4种 答案：B【分析】 根据常见物质的名称与俗称来分析解答 。 【详解】 苛性钠、火碱和烧碱都是氢氧化钠的俗称，纯碱是碳酸钠的俗称，所以 “苛性钠、烧碱、纯碱、火碱”四种俗称中所代表的物质有两种。故选 B。假定英语课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10 处语言错误，每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。增加:在缺词处加一个漏字符号(∧)，并在其下面写出该加的词。删除:把多余的词用斜线(\)划掉。修改:在错的词下面画一横线，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。Last October, we have had a series of reading activities. In the first two weeks, we read some great books. Among these books, I like The Old Man and the Sea better, from which I’ve learned never to give up when facing with difficulties. In the afternoon of October 18, we held a poetry contest. I recited a poem written by me and won first prize. At the end of the month, we acted out some famous work. My classmates and I performed The Million Pound Bank Note. To our great delightful, our performance was huge success. We both enjoyed such reading activities , wish to read more great books in the future.