Have you ever wanted to achieve something really amazing in life? Well, Greg Mortenson wanted to climb a mountain, but he ended up helping thousands of people to have a better life.

 Greg's story began with failure. In 1993, he set out to climb K2, the world's second highest mountain. But Greg never made it to the top.  After five days, he stumbled(踉跄）into the village of Korphe in northern Pakistan, injured(受伤）and hungry. The kind villagers there looked after him for several days.

 Greg saw that the villagers were very poor and hungry, and some of them were ill. Also, the village school didn't have a roof(屋顶）and the children wrote on the ground with sticks. Greg knew he wanted to do something to help. " I'll build you a school,”he told the villagers. “ I promise.”

 Greg went back home to the USA to raise money for the school. He even lived in the car to save money! Finally he went back to Korphe and built the school. But this was just the beginning of something bigger! Since then, Greg's organization has built around 80 schools and runs many others in Pakistan and other countries, too.

 Greg hasn't finished yet. He does many other things to help people in poor countries. He has got many prizes, but it's the smiles of the children he has helped that makes him happy!

 Greg has just written a best-selling book about his story called Three Cups of Tea. It's an interesting and exciting book which tells us what ordinary(普通的）people can do with courage and determination(决心）!

    It was Sunday morning. A butcher（屠夫） heard the doorbell and thought it must be a customer. But he was surprised to see that a dog was coming into his shop. The dog had $10 and a note in its mouth. The butcher took the note and read it. It said, "10 pork chops（排骨）, please." So the butcher took the money and put a bag of chops in the dog's mouth.

    Then he quickly closed the shop because he decided to follow the dog. He found the dog on the street. The dog was waiting for a green light. Then the dog walked across the road. The dog went to a bus stop. When a bus arrived, the dog checked the number and then got on the bus

    After a while, the dog stood up on his back paws（爪子） to push the "stop" button（按钮）.The bus stopped and the dog got off. Then the butcher followed it to get off the bus.

    The dog ran to a house and dropped the bag in front of the front door. It then began to beat its head against the front door. After a while, a big man opened the door and began shouting at the dog. The butcher ran up and shouted at the man, "What are you doing? Your dog is a genius（天才）."

    The owner of the dog said, "Genius? No way! I always tell him to take the keys when he goes to the stores. But he never listens to me! "

If you look at the top of your phone，you'll usually see a little symbol that says 3G or 4G. The "G" stands for the "generation（代）" of your mobile network. But the symbols will become things of the past after 5G networks fully arrive. Shanghai became the first city in China to start testing 5G networks. 

About 100 times faster than 4G networks，5G lets people download and upload data（数据） faster than ever before. But 5G doesn't just bring faster mobile internet. People can use it for many other things as well. For example，5G helps to make self－driving cars safer. 

5G could also be used to power the Internet of Things（IoT，物联网），that is，a large online network that connects all things and people. Fast internet speeds are the key to developing this technology. 

The IoT could be used in a lot of ways. For example，with IoT，your fridge could automatically（自动地） place an order online for eggs when it finds that there are no eggs left inside.