一元二次方程x²=2x的解是（　　）

新中国60周年国庆阅兵式中，100毫米突击炮、新型远程火箭炮、歼—10、空中预警机等一些新装备盛装亮相。追溯历史，中国是世界上最早发明火箭武器的国家。它们最早出现的时间应该是

材料一 唐太宗派兵灭亡东突厥，后唐朝又灭西突厥，设立了安西和北庭都护府。回纥、南诏的首领接受唐朝的册封，吐蕃与唐通婚，密切了唐朝与吐蕃的关系。

材料二 宋与周边少数民族政权之间战争频繁，屡战不胜，和辽、西夏、金议和。这使得宋和其他少数民族政权之间保持了长时间的友好交往。

材料三 蒙古等族人们成批迁往内地，汉族人也大量来到边疆，契丹、女真等族人民较早进入黄河流域，各族人民杂居相处，互相通婚，逐渐融合。

-----《中国通史》

材料四 清朝，西藏地区与中央政府的联系更加紧密，西藏喇嘛教首领五世达赖于清初到北京，受到顺治皇帝接见，被正式赐予“达赖喇嘛”封号。   

修改下列病句。

我的思路把清脆的鸟鸣声打断了。

   I will never forget the year when I was 12.My mother told us that we would not get Christmas gifts because there was not enough money .I felt sad and thought, ”What shall I say when the other kids ask me about my gifts?” I started to hope the Christmas wouldn't come that year. Just then three women came to our house with gifts for all of us. For me，they brought a doll .I felt so happy.
   Years later, my life changed a lot. So one Christmas, I wanted to do something special. I asked forty friends to help me. We visited 125 orphans(孤儿)to come to our Christmas party. For every child, we prepared a beautiful gift.
   Finally the moment came. I called out,” One, two, three. Open your gifts!” As the children opened their boxes, the whole room was full of their bright smiles. The feeling I got from that Christmas so long ago came again.