已知二次函数图象经过（2，﹣3），对称轴x=1，抛物线与x轴两交点距离为4，则这个二次函数的解析式为 _________ ．

VI.短文改错 8%（共8处错, 其中68题有7处错，划线处除外。）

67. _______. I don’t doubt whether it was German soldiers who stole the amber room.

68. _______The Great Wall, one of the wonder in the world, has a history of over two thousand years and covering most parts of the north of China. Because it is regarded as the longest wall in the world. Qing Shi Huang, the first Chinese emperor, keep the enemy out of his empire(帝国)，had all the walls join up. It really takesmillions of people many years to build it at that time. Today it has become a place of interest not only to the Chinese and to people from all over the world. As the famous saying goes, “He who does not reach the Great Wall is not a true man.”