Mr. King was the manager of a hotel. One weekend all the hotels in the city were full because there was a large meeting. On Friday night, three men came into the hotel and asked for rooms. Mr. King said there were no rooms ready because of the meeting. The men were unhappy.

    Mr. King wanted to help them. He remembered that Room 418, a very small room, was empty. He asked them if they would share a room. The three men said they would. Mr. King said the room would be thirty dollars: ten for each one. Each man gave him the money and then went up to the room.

    Mr. King soon began to feel sorry. "Thirty dollars is a lot to ask as price for that small room. " he thought. He called his assistant over and said, "Here is five dollars. Take it to the men in Room 418. I asked too much for their room."

    The assistant took the money. While he was on the way there, he started to think, "How can three men divide five dollars? I'll give them each only one dollar and keep the two dollars for myself. The men will be happy to get something back, and Mr. King will never know. " So the assistant returned one dollar to each man.

    Each man had at first paid ten dollars. After the assistant returned them one dollar each, each had paid nine. There were three men, $ 9 ×3 = $ 27. The assistant kept $ 2. $ 27 + $ 2 = $ 29

    Where is the missing dollar?

    Sarah is thirteen years old. She comes from Manchester in the UK; but now she is living in Geneva in Switzerland. Her father works for the UN and because of that she and her parents have to move a lot.

    Sarah has lived in five different countries: the US, Morocco, Turkey, Switzerland and the UK. But she doesn't remember the UK very well, because they moved to the US when she was only two years old. Still, she visits it often during vacation. She usually stays at her grandparents' house in Manchester. She likes visiting her grandparents, because they often take her to the Peak District National Park. It is very beautiful. Sometimes she stays with her uncle in the little town of Penzance in Cornwall. Sarah likes Penzance, too, but it's often very cold and windy. Penzance is very different from Geneva. In Geneva it is much warmer (更暖和的) in summer, but. also colder  in winter.

    Sarah likes going to new places. But every time she moves, she has to leave behind her old friends. She always needs to make new friends, and then leave them again. Luckily, they can write e-mails to tell each other about their lives.

I went to Grand Canyon (大峡谷) National Park in July 2012 for the firsttime and I knew I wanted to work there as a park ranger（管理员）. Park rangers protect the park's animals, plants, land, buildings, andpeople.

Now, as a park ranger forGrand Canyon National Park, I share the science, history and beauty of this parkwith thousands of visitors from around the world.

National parks are like outdoormuseums. Park rangers have all kinds of jobs, depending on where they work and whatthey studied during college. I teach school field trips（实地考察）, work at visitor centers and helppeople stay safe during their visit.

My favorite part of my jobis showing children their first look at the Grand Canyon during school field trips.Children are often amazed at the canyon's size and colors. Sometimes, they thinkit looks like a painting.

Being a park ranger requiresa lot of energy. I walk several miles and talk with hundreds of people each day.Park rangers must enjoy working with people and speaking in front of groups. Nearly5 million people visit Grand Canyon National Park every year.

Park rangers must also beprepared for any situation. Recently, I broke a traffic jam(堵塞). It was caused by a huge elk（麋鹿）standing in the road. Elks can become dangerous when they get scared,so I asked visitors to stop their cars and take pictures from far away. Believeit or not, I also help protect people from monkeys. It is not allowed to feed animalsin national parks. But sometimes, visitors try to feed monkeys.

My grandma moved to a new house. The houses in the neighborhood were all new and {#blank#}1{#/blank#} (look) the same. My brother and I planned {#blank#}2{#/blank#} (make) something special as a gift for Grandma's new house. We came up {#blank#}3{#/blank#} the idea of building a deck (平台) in her backyard (后院).

That day, Grandma was away with Jenny, one of her {#blank#}4{#/blank#} (neighbor). My brother and I started working. It was not easy to build a deck. We worked all day without {#blank#}5{#/blank#} (take) breaks. At last, we finished it and went home with satisfaction.

The next morning, we came to Grandma's home and {#blank#}6{#/blank#} (open) the back door. To {#blank#}7{#/blank#} (we) surprise, the deck was not there! Just then, Jenny came out and said, "Hey, look! Someone built a deck for my house."

{#blank#}8{#/blank#} (sudden), we realized that we built the deck in Jenny's backyard instead of Grandma's! {#blank#}9{#/blank#} we told the truth to Grandma, she laughed. Finally, we decided to build {#blank#}10{#/blank#} new deck for Grandma. We had a deck party after we finished working.

Maya and her parents are going to the United States to visit Maya's Aunt Vicky.

"Hurry up, Maya!" says her father. "We need to get to the 1 !" Maya has never been on an airplane before. She is 2 . Will the plane fall out of the sky? Maya's father finds her 3 under her bed. "What's wrong? Are you scared?" he asks. Maya nods.

"Planes are safe, darling. They are designed to fly!"

"But 4 ?" whispers Maya.

"Four forces are at work, keeping planes in the air." Maya's father 5 four fingers. "The sky is full of air, which pushes the airplane backwards. We call this DRAG. The 6 of the plane and everything inside it pulls it downwards, towards the ground. That's called GRAVITY (重力)."

Maya crawls (爬行) out from under the bed. She sits beside her father on the bed.

"A plane's engine works really hard to push the plane 7 . We call this THRUST. If the thrust is 8 than the drag, the plane flies ahead!"

"Cool!" Maya smiles.

"Finally, the wings of the plane are built so that the air on top of them moves faster than the air 9 them. The faster air is under less pressure, which lifts the plane up into the sky—it is called LIFT! I promise we'll be safe in the airplane," says Dad.

"When you put it that way, I can't wait to 10 !" Maya jumps up and takes her suitcase. "Aunt Vicky, here we come!"