题目

Dear Kitty, I’m happy to know that you like the storybook. And thank you for the red sweater. In Australia, we don’t have Mid-Autumn Festival. But we have Halloween (万圣节前夕) on 31st October every year. It’s an interesting festival. In the evening, our children dress up as witches (巫婆) ghosts (鬼) and animals. We play a game. It’s “Trick or Treat”. “Treat” means to give us sweets or presents. We will go from house to house and say, “Trick or Treat”. If someone does not give us sweets or presents, we will play a trick (捉弄) on him later. Many people pu10．写出一个二次根式使得它与$\sqrt{3}$为同类二次根式，这个二次根式可以是2$\sqrt{3}$；写出一个最简二次根式，使得它大于2小于4，这个二次根式可以是$\sqrt{7}$．