（A）

      Mary is an English girl, but shelives(居住) in China.She is six. Her mother says to her, "You are six now, Mary, you are going to school.I think it is very good. It's a nice school."

      "Is it a Chinese school?" Mary asks.

      "Yes, it is." Her mother says.

      It is September(九月) and the new school year begins. Marygoes to school every day. She likes her lessons（功课） and her classmates(同学)very much.Her classmates like her, too. Mary can speak a little Chinese. She likes China.She likes the people of China and Chinese food very much. 

化学用语是化学学科的专用语言，是我们学习化学的重要工具。请你从给定化合价的五种元素中，选择适当的元素，按要求写出相应物质的化学式(每空只填一种物质)：单质  ____ ；金属氧化物____ ；可作为复合肥料的盐____  。

神经调节的基本方式是（ ）