You have probably heard the expression, "It's raining cats and dogs outside." It means that it's raining very hard but not that 1 cats and dogs are filling from the sky. 2, one day in June, 1882, it really did rain 3 over Dubuque, Iowa. The frogs began falling along with hailstones (冰雹) during a 4 storm.

    Hail is 5 when drops of rainwater are caught by heavy winds and are carried high up into the air. There the raindrops become 6. Many drops may freeze together to form 7 of ice; these ice balls, or hailstones, then 8 to earth.

    During the storm in Dubuque, the strong winds 9 small frogs from nearby ponds into the air along with raindrops. When some of these frogs became covered 10 ice, both hailstones and "frog-stones" fell onto the ground.

    Each one of us shares this planet with over seven billion others. And we all need1. People and products need to move from city to city and country to country. However, we all know2most cars, motorcycles, boats and planes cause air pollution. They are also3. This is a serious problem in many cities.4inventors are coming up with creative ideas to try to reduce the pollution and noise.

    In many cities around the world, motorcycles are very5. Now Vietnam has around 33 million motorcycles and China has almost 120 million. Motorcycles are a faster and cheaper way to get around a city than6. Yet air pollution is a growing problem. In large cities, people7it is difficult to breathe. To solve these problems, an American company designed an environmentally friendly motorcycle. It uses electricity as fuel (燃料). As a result, there is8pollution. It's also quiet and fast. This makes9a good choice for getting around a city.

    The Italian city of Venice is a city with only a few10. There are no cars in the city centre.11cars, water taxis and buses carry people along the city's canals (运河). However, they cause pollution,12to the water. English engineers Dick and Jem designed a solar-powered (太阳能的) water taxi. The water taxi13run for a day after being charged (充电).

    Planes also cause air and noise pollution. Designing an environmentally friendly airplane is a real14. Some airplane companies have15to solve the problems. Swiss engineers have gone one step further. They developed a solar airplane. This airplane even tries to travel around the world.

It was the summer before my third grade. Our girls' softball(垒球) team was facing real pitchers(投球手)1 the first time. Before that, we could just hit the ball on the tee (球座). When the coach started pitching, hitting became 2 for me. I missed every single pitch. From the side, I heard my teammate Emily laughing at 3 . My face turned red. At that moment, I was starting to 4 playing softball.

The next afternoon, when Mum said it was time to play the game, I told her I was 5 . She allowed me to rest for a while. So I went to my room and 6 myself in bed. This was difficult for me because I was OK and just 7 to keep away from softball.

Soon Mum came in and said, "Time to go!" She didn't even ask if I felt 8 . I imagined Emily laughing at me, and 9 I really did feel sick to my stomach. I began crying loudly. Still, Mum pulled my team T-shirt over my head. She said, "You have to 10 for the rest of the season, and only after that can we talk about 11 you'll go on next year." She added that practice was what I needed, not 12 . She promised to practise with me.

I got two hits that afternoon, and Emily didn't make a 13 . Every week after that, I practised at home 14 I got to be one of the best hitters on the team.

That 15 taught me being afraid is part of life, and I can do whatever is expected of me if I keep working and practising.

BIRO was the{#blank#}1{#/blank#}（invent）of the ballpoint pen. He was born in Budapest，Hungary. In the 1930s，when he worked{#blank#}2{#/blank#} a newspaper editor，he used a fountain pen almost every day. {#blank#}3{#/blank#}，he had to refill it all the time. The ink also did not dry{#blank#}4{#/blank#}（easy），and it sometimes{#blank#}5{#/blank#}（make）a mess on the paper. BIRO wanted a better pen. His brother，George，decided{#blank#}6{#/blank#}（help）him develop a special ink. The ink dried soon. Then both of{#blank#}7{#/blank#}（they） developed a new type of pen together. There was{#blank#}8{#/blank#} tiny ball at the tip of the pen. The ball rolled ink onto paper as it moved. They called the{#blank#}9{#/blank#}（success）invention "ballpoint pen". Everyone enjoyed{#blank#}10{#/blank#}（use）it. 

I'm Karol, a 19- year- old student from Honduras. For me, volunteering has been like a school of life where I' ve learned a lot about myself . When I was 13, I started my volunteer work by{#blank#}1{#/blank#}(修理) bikes. In the neighborhood, I took {#blank#}2{#/blank#}(无论什么) action was needed to help others.

 Then one day, a local woman, Amelia. asked me {#blank#}3{#/blank#} (回复) to her daughter. She couldn't complete it because she was {#blank#}4{#/blank#}(不能做某事的) to read and write. Her daughter was studying {#blank#}5{#/blank#}(在国外) in an eastern country for years, so Amelia missed her very much. In the letter, she told her daughter that she was better after the {#blank#}6{#/blank#}(手术) , which made her daughter not so worried." Thank you for helping me. It's you who came to help me to do it." Her words made me realize the importance of my work.

 Later I {#blank#}7{#/blank#}(继续) to help people in need after I joined a worldwide volunteering organization at 17. The experience has influenced me deeply because all the people I've met there have taught me how to learn from others and work together to finish {#blank#}8{#/blank#}(任务). I have learned the meaning of" being together" after seeing so many people try their best to build a better world.

 In my {#blank#}9{#/blank#}(看法) , to be a volunteer has been like a rebirth for me. It's{#blank#}10{#/blank#}(必要的) than ever for us to realize that a tiny step can make a big difference.

 On December 17, 1903, Wilbur and Orville Wright made the first successful powered flight in history, making their dream come true.

 It all started when Orville was 7 and Wilbur was 11. Their father gave them a toy helicopter(直升机), which made them dream of flying. Their mother, who knew much about machines and science, also influenced them a lot.

 When the brothers grew up, they entered the printing business. Then they opened a bicycle repair shop. It wasn't long before they were making their own bikes. However, the brothers never stopped to study flight. They studied what other people learned about flight. By 1900, the Wright brothers were ready to test their first Flyer. They tried many times. Finally, on December 17, 1903, they achieved success.

 That day, the brothers flew four times. Orville flew the Flyer the first time. That flight lasted 12 seconds and went 120 feet. Their second flight went 175 feet and the third 200 feet. Wilbur flew the fourth flight. It reached 852 feet in 59 seconds. After that last flight, the Flyer became too broken to fly again because of the strong wind.

They kept testing new designs to improve their Flyer. Later they began to teach others to fly. They even opened their own flying school. The brothers did make travel more convenient for people.