Height is just one of the features your genes(基因) decide. In fact, because you have two parents, your genes provide you a height that usually lands somewhere between the height of each parent. If both your parents are tall, then most probably you will be tall, too. But if you have questions about how tall you're going to be, ask your doctor if he or she can help you find them out.

    But genes don't decide everything. For example, eating an unhealthy diet can keep you from growing to your full potential(潜力). Getting plenty of sleep and enough exercise will help you grow to the expected height.

    It's natural that you're wondering how fast you should grow. There's no perfect or right answer. Generally speaking, kids grow about 6 cm a year between age 3 and the time when they start puberty.

    Your doctor will know how your growth has been going over the years. 2 cm here and 3 cm there make a little difference to the height you're at now. How have you been growing up to this height? What other changes may your body be going through?

    Don't be amazed if you seem to have grown a lot in a very short time. Everyone has a growth spurt(高峰) during puberty. The age for starting puberty is about 10 for girls and about 11 for boys. But it can be earlier or later — between 7 and 13 for girls and 9 and 15 for boys.

    You'll usually begin to notice that you're growing faster about a year after your body starts to show the first changes of puberty.

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    Which animal do you think is "the king of the animals", the elephant, the lion or the tiger? They are all large and strong. But I think the tiger is "the king of the animals". If you watch carefully, you can find some black lines on the tiger's forehead(前额). The lines look like the Chinese word "WANG". The word means "the king of the world" in Chinese.

    Most of the tigers come from China and India. Tigers are dangerous animals. They look scary(吓人的). They like eating meat. They have yellow fur with black lines. They usually weigh about 200 to 300kg. Tigers can run fast. They run at a speed of 20 meters per second.

    Some people think they are dangerous. But they don't know tigers are in danger now. There are only 20 to 30 wild South China Tigers in China and less than 300 in the world. Lots of people kill them for their fur. We should take action to protect them.

You can learn a lot in a club. After you join a club, you can know how to play basketball, how to cook or how to speak English. These new things make you better. Also, good chances like a basketball match, a music festival or an English show, are easy to get when you are in a club. 

In a club, you can meet new people and make friends with them. Then, you can play games and have a great time with them. They can be your teachers too, and you can get new things from them. 

At last, joining a club makes you busy. You always have things to do, so your life will be quite interesting. 

①Yellowknife, Whitehorse and Come By Chance — all are names of towns and cities in North America. Ottawa, Beijing, Paris, Hanoi and Tokyo — all are important world cities. But how did they get these names? And why?

②Some names sound funny, and some of them make no sense when you first hear them. But there is always a story or a tradition behind a name. People live in an area. A city begins to grow. In the beginning, it might have no name, but soon, people start calling it something. When enough people use this name, it usually sticks. And a new city name is born.

③In the tradition of East Asia, important cities are given names that tell us exactly what they are, and where they are located (位于). Nearly everyone will know that Beijing means "northern capital". But do you know that Tokyo and Hanoi mean "eastern capital"?

④Ottawa, Canada's capital city, was given its name thousands of years ago. It is located at a place where two rivers meet, and was a place where Indian nations came to trade with each other long ago. In the native (当地的) language, Adawe means "to trade". When the Europeans lived in the area, they heard the natives calling the place Adawe. This sounded like Ottawa to the European ears. Soon enough, everyone was calling the city Ottawa.

⑤When a European explorer (探险家) arrived at a place in the far northern area of Canada, he found native people carried huge knives made of copper (铜), which appeared yellow in the shining sun. The explorer decided to call them Yellow knives. He named the place where they lived Yellowknife.

⑥Next time you hear an unusual city name, see if you can discover how it got that name.

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Welcome to the Zoo

 Come and meet the Indian elephants and the new tigers from America. The bears are waiting to meet you, and you can also see the monkeys from China. The lovely dogs from Australia are waiting to laugh at you. The giraffes from Zambia are waiting to look down on you.