Now many people like to keep dogs as their pets. But how did dogs become humans' close friends?

    In some places of Europe (欧洲), about 10,000 years ago, some wild (野生的) dogs often came to human's houses to find food. The wild dogs looked different from the ones today. They looked like wolves (狼). At first, they felt ① frightened. They always stood and looked for a short time. Then they got the food and ran away. Sometimes the young dogs couldn't run fast and people caught them. People trained them and the young dogs grew up with the help of people. Slowly, the wild dogs became home dogs. They could make home safe when people were away. They helped people hunt (狩猎). They helped people keep warm on cold nights. ② Sometimes, they could smell and hear danger before people could. In some cold places, they helped people pull (拉) things people need.

    Now there are more than 400 different kinds of dogs in the world. And they look different from each other. The number and kind are growing all the time. Today, some people mainly (主要地) regard dogs as pets. In fact, dogs are really our close friends. We should protect them from being killed.

    Bikes and cars are two important things. Many Chinese people have cars now, but most Chinese people still like to ride bikes. Do you know why?

    We all know that the bike can't go quickly, but it's easy for people to buy and ride it. As for the car, it needs too much money.

    Most Americans live far from the center of cities or their working places. So they need cars to go shopping or go to work every day. Most Chinese people live near their working places, so they don't need cars to go to work. And it's good for the environment(环境) if people stop driving. So there is a day called “No-Car Day” on September 22^nd every year.

    For me, I like to go to school by bike. It is easy and healthy.

    Wang Yaping taught Chinese primary and middle school students on Earth physics problems in the zero-gravity environment(失重环境).She prepared for the lecture for a long time.

    Wang, born in January 1980, is from east China's Shandong Province. She was a pilot in the People's Liberation Army Air Force(空军)with experience of 1,600 hours of flying.

    The world's first teacher in space was Christa McAuliffe, a 37-year-old middle school teacher from the United States ,but the Space Shuttle Challenger（挑战者号）disintegrated(崩裂)after 73 seconds into flight on Jan.28,1986. McAuliffe and other six members were killed.

    “Wang's lecture was a pleasant surprise,” said Zhang Xiaguang, an astronaut in the three members of shenzhou 10 spacecraft.“________________(她无论做什么都很优秀).Sometimes we'd like to give her a helping hand ,but she just would not take the hand in help,”said Nie Haisheng.

    Like many young Chinese people, Wang likes photography, music and basketball. She said ,“We are all students in facing the universe(宇宙)。We are looking forward to joining our young friends to learn and explore the mystical(神秘的)and beautiful universe.”

    In the United States, teenagers (青少年) can only get a full-time(全职的)job if they are 16 years old or older. But there are things that the younger teeagers make some money. Here are a few examples.

    Parents will young children sometimes want to go out for dinner or to the movies, but they don't want to leave their children at home alone. So they ask a teenager to stay in the house and look after their children when they are out. If the children go to bed early, the teenager can do some of his or her homework!

    Some people have a dog, but they don't have time to take it for a walk. Dogs need a lot of exercise! So some teenagers work as dog walkers. It's a good idea -- they can make money and stay outside in the fresh air. They get some exercise too!

    Teenagers can deliver (递送) newspapers. They usually ride a bike and leave newspapers at each house. They need to have their own (自己的) bike. They have to get up early too, because people want to read their newspapers at breakfast.

    Teenagers can also work at home on their computers. Some companies pay teenagers to take online surveys (调查). They want to know what teenagers are interested in. It's a fun and easy way to make money.

    These are all popular jobs.青少年可以选择™中的一个来赚些钱 Before they do their jobs, they usually tell someone about what they' re doing Being safe is the most important thing after all.

    It may take a long time for some people to learn to speak English. However, by following these tips（实用的提示） you should be speaking English in no time.

    Tip I: Forget about having a large vocabulary. Only learn the words you will need most. For example, if you are traveling in an English-speaking country, make a list of all the possible sentences and questions that you would need to know, such as "Do you know where the nearest bathroom is? "and" I am lost. Can you help me?" Think about what sentences you would want a traveler to know if they came to your country and couldn't speak your language.

    Tip 2: Once you have a list of vocabulary that you think will be most useful to you, make sure you understand the meaning of each word and know how to use each word in a sentence. Try making lists with new words and sample sentences(例句). Ten new words is enough on each list. Then stick(粘贴)the lists up all over your house where you can easily see them. Practice every day. Whenever you see a list, make sure you stop and read through it.

    Tip 3: Now pronounce these words and sentences properly. Try to learn pronunciation by listening to how English speakers pronounce words. Watch English TV shows, listen to English radio programs and try to talk with as many English speakers as you can, online or in person.

    I wish you the best of luck and I hope my tips are helpful!

    Everyone cares about his or her image(形象). What about you? {#blank#}1{#/blank#} Have you ever done the following little things to hurt yours?

    You don't let people get out of buses or elevators before you get in. It is not good to push yourself into the crowd who's trying to get out anyway. {#blank#}2{#/blank#}

You don't cover your mouth while coughing. According to Live Science, one cough can release(释放) as much as 3,000 droplets of saliva(唾沫星子),{#blank#}3{#/blank#} Covering your mouth is not a choice but an absolute must.

    {#blank#}4{#/blank#} You think your music taste is great? Perfect, go to study music, to become a DJ, but please don't push your music taste onto other people.

    You are rude to waiters. Imagine working for 12 hours, always on your feet, and then dealing with the most rude customers? Yeah, don't be that person who thinks waiters have to deal with your bad attitude.

    Common sense not so common. {#blank#}5{#/blank#}

A. You listen to music without headphones.

B. Some little things can hurt your image.

C. Some serious things may hurt your image.

D. And they can fly as fast as 50 miles per hour.

E. Don't mind your behavior and do as you like.

F. Just stand aside, let people out, and then get in.

G. Please watch your behavior and be polite in public.