2019年12月18日，连接青海格尔木与甘肃敦煌的敦格铁路全面建成通车。读敦格铁路示意图和敦煌莫高窟景观图，完成题目。
敦煌莫高窟是世界文化遗产，下列行为可以更好地保护和发挥莫高窟价值的是（ ）
敦煌莫高窟是世界文化遗产，以上四种做法中，规划重建新石窟、大力开发旅游项目和关闭石窟都不利于保护和发挥莫高窟的价值，只有对游客数量进行控制才有利于保护石窟，故选D。
Dogs are the best pets of humans. They come in all sizes. Some dogs are as small as a football, and others are as tall as a desk. Dogs’ fur (毛) is different, too. It can be long and soft, or smooth and hard. People don’t mind the kind of fur, because all dogs are good to hug.
请在字典中查一下这个词。
我喜欢甜食， 你知道的。
去年， 彼得在旅途中和许多人交了朋友。
我叫托尼· 史密斯， 史密斯是我的姓。
我们在课上回答问题时应该起立
Tea and coffee are two of the most popular drinks in the world. However, people usually like one more than the other. These drinks also have very different uses.
People in the office usually sit for most of the day when they work. But this is bad for a person’s health. When people sit for too long every day, they don’t move very much. So it is easy to start getting fat. Sitting too long is also bad for their work because it makes them want to sleep. When this happens, people may make more mistakes in their work or spend more time finishing their work. Companies need workers to be healthy, so how do they fix the problem?
