阅读材料，回答下列问题

材料一：在西北面，击退了游牧部落；为了防止他们卷土重来，还修筑了世界闻名的长城。为了完成这一巨大工程，耗去了大量生命，以致2000多年后的今天，人们仍要谈起这一事实：有100万人为修筑长城而死去，长城的每一块石头都值一条人命，老百姓都为筑长城的事咒骂皇帝。

材料二：西晋时，内迁的少数民族学会了汉族的农业生产技术（如下图）

材料三：禁用鲜卑语，统一使用汉语，……30岁以下的人和在朝廷做官的人，不得继续使用鲜卑语，明知故犯，就要降职或罢官。

   The best way of learning a language is using it .The best way of learning English is talking in English as much as possible. Sometimes you'll get your words mixed up ( 混合)and people will not understand you .Sometimes people will say things too quickly and you can't understand them. But if you keep your sense of humor (幽默感),you can always have a good laugh at the mistakes you make(你所犯的错误). Don't be unhappy if people seem to be laughing at your mistakes（错误）. It is better for people to laugh at your mistakes than to be angry with you. because they don't understand what you are saying .The most important thing for learning English is : “Don't be afraid of making mistakes because everyone makes mistakes. ”