Have you ever counted the number of digits (数字) in your mobile phone number? Your number has 11 digits. You may sometimes find it hard to remember your number. That's because China has the longest mobile phone numbers in the world. Why is that?

    The 11 digits can be divided into three parts. Each part has a different meaning. The first three numbers tell you which mobile phone service company it is. For example, 135 is for China Mobile Communications

    Corporation and 188 is for China Unicom. The fourth to the seventh digits tell you where the number is registered (注册). And the last four digits are random (随机的).

    The main reason for using 11 digits is that we have the largest population in the world. We once had 10 numbers. But as our population grew, there were not enough numbers for us to use. So we began to use 11 digits starting from 1999. Eleven digits can be used to make tens of billions of mobile phone numbers. That's enough for each person to have seven or eight phone numbers to use in China.

    And mobile phone numbers can be recycled. Usually, the service company will reuse a canceled number after three to six months. If you call a number that you haven't contacted for a long time, you may find that its owner has changed.

    Besides China, Britain and Japan also use 11-digit mobile phone numbers. But their numbers always start with 0. So they cannot create as many numbers as we can. Countries like the United States, Australia and India use phone numbers with 10 digits. Canada's mobile phone numbers are perhaps the shortest in the world: they use seven digits.

    When you are in a group with good classmates, it can be very good for you. You should always be prepared when going to school, but there are days when you forget a pencil or a notebook. You can then borrow one from your classmate. If you're having trouble understanding a certain question, classmates can be quite helpful. Having a difficult math problem explained to you by a fellow student will be much easier than asking your teacher, because your teacher can't be always with you. Some teachers will not tell you homework if you've missed a class. Having a classmate who will let you review his note can help you a lot in a situation like this. If you happen to have a classmate who lives nearby, you might be able to carpool (拼车) to and from school. Not only will this save some money, but also it will help protect the environment as well. Students who enjoy their surroundings and get along well with their fellow classmates are usually much happier than those who are not.

Good morning! I'm Zhang Han. I'm a student of Yujiang Middle School in China. The school is nice. 

I'm in my 1 now. This is a desk. The 2 of the desk is blue. It is Lily's desk. Brown is her last name. Lily Brown is my good friend. She's from England. So she can speak 3 well. Look!A set of keys and a schoolbag are on the desk. The keys are yellow. They are Lily's. The4 is blue. Is it 5 , too? No, it's my schoolbag. 

6 desk is next to(挨着) Lily's? It's mine. It's red. What's 7 my desk? Two pens are on it. The first pen is mine and the next pen is Li Ting's. Who is Li Ting? She is my good friend, too. She is a nice girl and she often(经常)8 me at school. Can you see a watch on the desk?I9 it in Classroom 2A this morning. Is it yours? Please 10 me at zhanghan@ gmail. com. 

In April, the world heard some bad news：Japan will dump （倾倒） nuclear （核） wastewater into the sea in two years!The Japanese government （政府） said it was 1 to do this. 2 everyone worries about what will happen if the wastewater enters the sea？It might be dangerous. 

The wastewater will first 3 the sea around Japan and its neighbor countries 4 China and South Korea. It will go to most of the Pacific Ocean in 57 days. And in three years, it will 5 the US and Canada. The sea covers 71% of Earths surface. So the wastewater will go to most parts of the world. The radiation （辐射） could stay in the sea for thousands of years!

Is nuclear power a/an 6 thing？This answer is "No". Nuclear power can 7 us with electricity （电） and heat. It also powers trains, planes and aircraft carriers. 

However, radiation is bad for humans, sea animals and plants. For example, it can cause （引起） some fish to 8 or even die. If you eat these fish, radiation will enter your body, too. Can we eat safe and healthy 9 in the future？Maybe people will 10 eat it if Japan dumps nuclear wastewater into the sea.