Last week, I drove from Los Angeles(洛杉矶) to Dallas(达拉斯) with my daughter. Unluckily, we ran out of gas on the way and we couldn’t see a gas station.

My daughter came up with an idea. She wrote a sign that read “No gas. Can you help us?” and put it outside the window. She hoped that a driver would stop to offer help when he saw it.

There were few cars at that time. About an hour later, a car passed by us quickly. We thought it drove away. Instead, it stopped and a man got out and walked up to our car. The man thought we had no money to buy gas, so he gave 20 dollars to us. When he knew what the matter was, he said, “My farm is about 10 minutes away. If you give me 20 minutes, I will be back and get a can of gas for you.”

Sure enough, the friendly man was back with the can quickly. We tried to pay for the gas, but he refused. “Everyone should help those in need,” he said.

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Aliens have always been full of mysteries. However, people from different parts of the world have alien abduction(绑架) stories to tell. Most of their alien abduction experiences have much in common. For example, most alien abductions are said to have taken place at night and the abducted people are mostly said to experience a medical examination. Interestingly, all the abducted people have returned safely to the earth. Some people consider these stories as rumors, while some choose to believe that they were real. Here are two famous alien abduction stories.

One was that of Betty and Barney Hill. On September 19, 1961, they were in a car to Portsmouth of Britain when they saw a bright light in the sky. Soon some aliens got out from a UFO and drew near the Hills. The aliens soon abducted them.

The other famous story was that of Villas Boas. Villas Boas was a Brazilian farmer who was working at night on October 16, 1957 when he saw a UFO with a red light in the night sky. He began trying to run from the object that seemed to be drawing near him. But he was soon abducted by an alien. He was taken into the UFO, and a blood examination was performed on him. When he returned to the earth, he realized he had been abducted for four hours.

Today, experts guess that over 50% of people worldwide live in cities. By the year 2050, they expect 70% are going to be living in cities. They also say that more of the world’s cities will be megacities!

A megacity is a huge city. It might be any city with over 10 million people. However, it is harder to count the exact number of people living in a city than one might think. For one thing, it is not always clear who to count. For the other, many megacities do not have clear borders(边界) for where the city ends. Suburbs and regions around the city may or may not be included in the city’s total population.

Even with the difficulty of saying where a city ends and who to count, it is clear that certain cities around the world are megacities. Sao Paulo, the city with the most people in South America, is one, New York, the most famous city in North America, is another. Then there is Tokyo, a megacity with over 30 million people. This makes it the largest megacity in the world.

A mega-region, develops when megacities become so big that we can consider them to be connected. One report by the United Nations said the largest mega-region today is in China. The megacities included in this region are Hong Kong, Shenzhen, and Guangzhou. However, a mega-region does not have to be limited to one country. In West Africa, a mega-region connects four countries: Nigeria, Benin, Togo, and Ghana.

An important fact about mega-regions is how much economic power they have. Research by the United Nations found that 66% of economic activity worldwide happened within the world’s 40 largest mega-regions. The research also showed that 85% of new ideas in technology and science came from these 40 mega-regions. Less than 20% of the world’s population, however, lives in these mega-regions.

I Am a Pencil (Price:$59.88)

The writer of this book, Sam Swope, took a job to teach writing in New York City.     46     But there were a few things they had in common: family troubles, money making and interest in poems. Every student made great progress in writing with the help of this teacher. Swope tells readers that everybody is a poet in their deep heart.

What It Takes to Pull Me Through(Price:$35.86)

David L. Marcus takes us inside a boarding school(寄宿学校) for troubled teenagers. He shows the great pressures that are put on these teens and made them lose their confidence.     47    

The Most Scenic Drives in America(Price:$47.88)

This travel book has been put into several languages.     48     It has over 200 photos of wonderful places. It also provides maps, the new information about those places, and advice on travel.

Our Brother’s Keeper(Price:$59.40)

Writer Jedwin Smith spent many years trying to forget the memories of his brother. Jeff, who was killed. But in this book, he tells what happened when he met several of his brother’s old friends.     49     They also went on a trip to Vietnam, to visit the place where Jeff died. There,a lot of stories happened...

There are more books on show.     50