题目

已知短周期元素的离子aA2+、bB+、cC3-、dD-都具有相同的电子层结构,则下列叙述正确的是(   ) A.原子半径: A>B>D>C       B.原子序数: d>c>b>a C.离子半径: C3->D->B+>A2+             D.单质的还原性: A>B>D>C 答案：C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。错误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。 I happen to meet some American tourists at the gate of the Summer Palace last week. I greeted them with English and then we began to chat. I got to know that they were college student traveling in China. Most of us were fond of Chinese medicine. They were busy taking pictures and were surprising at the changes had taken place in the past few years. After that, we went boat and had a good time. We were exchanged our e-mail addresses so that we could write to each other in the future. They thanked me again and again. I was gladly to have a chance to practice my oral English. What wonderful experience !