Dear friends,
   My name is Helen. I'm 12 years old. I  1  from Taxas, America. I’m really  2   in Chinese geography. It's fun! And I hope you can tell me more. I like hamburgers best,  3   I try to eat them twice a week  4   it's a kind of   5   food. And I like to drink lemon  6   . As for sports, I often go swimming with my parents on weekends.
   I   7  in Cobb Street School. My   8  subjects in school are ME and art. They are really fun! After school, I like to go to the   9   with my family or friends. I like action movies and cartoons. They’re  10   How about you? Do you often go to the cinema with your family or friends?
                                                                                                                                                                   Yours,
                                                                                                                                                                   Helen

材料一

材料二 “今师异道，人异论，百家殊(异)方，指意不同”，人君就无法维持统一。“凡不在六艺(六经)之科、孔子之术者，皆绝其道，勿使并进”。

——董仲舒

请回答：

 用化学用于填空：

（1）氢原子____ 

（2）2个二氧化硫分子　____ 

（3）3个铵根离子　____ 　

（4）氧化铁中铁元素的化合价　____ ．

新中国成立后，为巩固、建设新生政权做出了一系列的努力。下列事件按时间先后排序正确的是（    ）

①西藏和平解放  ②“一五计划”开始实施  ③抗美援朝战争爆发  ④土地改革基本完成