Snow falls in the Earth's extreme North and South throughout the year. However, the heaviest snowfalls have been reported in the mountains of other areas during winter. Snow is even known to fall near the Equator (赤道), but only on the highest mountains.

    Snow contains much less water than rain, but much of the water the world uses comes from snow. {#blank#}1{#/blank#} In the western United States, mountain snow provides up to seventy-five percent of all surface water supplies.

    Snowfall helps to protect plants and some wild animals from winter weather. Fresh snow is made largely of air trapped among the snow crystals (晶体). Because the air has trouble moving, the movement of heat is limited. {#blank#}2{#/blank#} The surface of the snow takes in, or absorbs, sound waves. As snow grows older or if there have been strong winds, it can become hard and flat. Then, the snow's surface will help to send back sound waves.

    {#blank#}3{#/blank#} It is responsible for the deaths of hundreds of people. Many people die in traffic accidents on roads covered with snow and ice or from being seriously stuck in the winter storm. {#blank#}4{#/blank#}.

    People may not be able to avoid living in areas where it snows often. However, they can avoid becoming victims of snowstorms. People should stop driving and stay at home until the storm has passed. People living in these areas should carry emergency supplies in their vehicle. {#blank#}5{#/blank#}

A. These include food, emergency medical supplies, and extra clothing to stay warm and dry.

B. Snow also influences the movement of sound waves.

C. Melting snow provides water for rivers, electric power stations and agricultural crops.

D. Mountain snowfall is heavier than that in the South and the North Poles.

E. In many places, streets were blocked; houses fell down and supplies were short.

F. Others die from heart attacks caused by too much physical activity out in the cold.

G. Snow may be beautiful, but it can be deadly.

    We all know that bullying is when someone is trying to embarrass, frighten or harm someone else on purpose. In cyber bullying (网络欺凌)you often don't know who the bully is. {#blank#}1{#/blank#} Cyber bullying uses technology.

    Mobile phones: text messages, pictures, video clips can be sent to you and all your friends very quickly but you don't know who is sending it.

    Internet: emails can be sent from an address which doesn't give the name of the sender. They can be messages, threats, rumors and lies about you. {#blank#}2{#/blank#}

    Websites: exist where you can talk about anything, post pictures and ask for comments. Some cyber bullies use these to embarrass or hurt their victims.{#blank#}3{#/blank#}

    Choose carefully who you give your mobile number, phone number and email address to.

    Always remove any addresses which are on an email you receive before sending it on to someone else.

    Don't use your real name when going online.

    {#blank#}4{#/blank#}

    What to do if you are being bullied in this way

    If you are the victim of cyber bullying, then tell. {#blank#}5{#/blank#}

    Your parents may report the matter to your Internet or mobile provider who will have some ideas about what you can do.

    Don't go in for cyber bullying yourself if you feel that you know who is doing it. Two wrongs don't make a right!

    Your parents can contact any regular site which displays embarrassing pictures of you and ask for them to be taken off

    If things are being said or shown about you on a personal website then you may need to turn to police for help.

A. How to punish the bully.

B. How you can protect yourself.

C. Ask your friends to do the same.

D. Never give out your internet password to anyone.

E. Tell adults, parents or teachers and keep on telling until something is done.

F. The bully can hide his or her information and make your life terrible── from a distance.

G. They may be embarrassing pictures that someone took on their phone or camera without your knowing.

    Radar is an electronic device that detects planes, ships, coastlines, landmarks, and even storm clouds. The name radar comes from the first letters of the words radio direction and ranging. As the human eye uses light waves to see, radar "sees" with radio waves. Without radar, planes could not land safely in bad weather and ships could not move safely in thick fog. {#blank#}1{#/blank#}

    In the 1800s it was discovered that radio waves could be reflected from objects. But scientists did not make great advances in radar research until the 1930s, when the world was threatened by war.{#blank#}2{#/blank#} It has been used widely in almost every conflict since then.

    Echoes make it possible for radar to work. When a beam of radio waves is sent out, it strikes on an object and returns an echo. This echo is picked up by radar and recorded on a screen similar to television screen. On the screen an observer sees a flash, or a blip, that shows the direction and distance of the object. {#blank#}3{#/blank#}

    Airport control towers use radar to guide planes in for safe landings. Almost all large ships depend on radar to prevent collisions with icebergs or other ships. {#blank#}4{#/blank#}Weather forecasters "see" the size, direction, and speed of storms on radar screens. Astronomers can even use radar to measure accurately the distance to the moon. Thus, the device has generated major advancements.

    {#blank#}5{#/blank#}Huge radar antennas have been installed all over the United States. They guard us against possible enemy attacks. We have ballistic—missiles (战略导弹)warning systems that can alert us to attacks when missiles are more than 1,000 miles away. Other radar systems warn us against enemy aircraft and even spying space satellites.

A. Police track speeders in radar-equipped cars.

B. These measurements are now highly accurate.

C. The device can be used in a wide range of fields.

D. It is therefore especially valuable to shippers and travelers.

E. During World War II many countries used radar effectively.

F. Today radar is used by commercial airliners and weather forecasters.

G. Strengthening national defense is one of radar's most important functions.

    You probably know that exercise is the key to reducing depression, but you might not know why. Here are some tips for exercising when you're depressed.

    Change your view of “exercise”.

    Forget “exercise”. Instead, think “being active” or “having fun”. {#blank#}1{#/blank#} Besides, it gives you a bigger benefit.

    {#blank#}2{#/blank#}

    Taking part in physical activities with others supports you in doing those activities. Ask friends what activities they're doing or they would like to start doing, and join them. Other choices include hiring a personal trainer, joining an exercise group or going to a class.

    Try an experiment.

    {#blank#}3{#/blank#} Or go to the gym every Monday, Wednesday and Friday. Even if you're feeling too tired to do any actual exercise, still go to the gym, park your car, walk in, chage into workout clothes, and pick up a 5-pound weight. If you're really so tired that you don't want to do anything else, that's totally fine.

    Take it outside.

    Nature has a great effect on our feeling and decreases depressive symptoms. Even just looking at images of lakes and trees helps. {#blank#}4{#/blank#} Or walk on a treadmill (跑步机) by a window.

    Tie it to a goal.

    Korb said, “When you connect your exercise to a long-term goal, it helps your brain forget momentary discomfort and makes your exercise more satisfying.” For example, Korb started getting active because it made playing sports more enjoyable. Figure out what's truly important to you. {#blank#}5{#/blank#}

A. Move with someone else.

B. Sign up and go to exercise classes.

C. It's a lot easier to do something simple.

D. Remind yourself of your goal regularly.

E. Remember your partner to keep you company.

F. Take a walk around your neighbourhood or a local park.

G. This increases your chances of actually moving your body.

    There have always been a lot of commonly believed but false ideas about being fat and doing exercise. {#blank#}1{#/blank#} While others hold that if they stop exercising, their muscles will turn into fat. Here are some more myths(缪见):

    I'll never lose weight—I come from a fat family

    Wrong! While we can't change the body type we are born with, we can't blame our genes for making us fat. There's plenty of evidence that fatness runs in families.{#blank#}2{#/blank#}

    {#blank#}3{#/blank#}

    Wrong! Fatness is not caused by a slow metabolism(新陈代谢). In fact, although fat people consume more energy than slim people, they also fail to realize how much they eat! Keeping a diary can help you work out your daily food intake more accurately.

    Exercise is boring

    Wrong!{#blank#}4{#/blank#} The key is to develop a balanced and varied program that's fun as well as progressive. If you enjoy a Sunday walk, take a different route. If you do yoga, try a tai chi class. If you like swimming, set yourself a distance or time challenge.

    No pain, no gain

    Wrong! Exercise is not meant to hurt. Indeed, pain is your body telling you something's wrong, and continuing to exercise could lead to serious injury. You may experience mild discomfort as you begin to exercise regularly, but this is your body adapting to the positive changes in your lifestyle and the aches should disappear relatively quickly.{#blank#}5{#/blank#}

A. And the main reason is that they share the same habits of eating too much and exercising too little.

B. I am fat because I burn calories slowly.

C. Anything will be interesting if you do the same kind of exercise.

D. If they don't, rest and seek medical advice.

E. And the main reason is that their parents are fat.

F. Anything will become boring if you do it repetitively.

G. Some people believe that they can't help putting on weight as they get older.

Kids are begging parents for cell phones at younger and younger ages, leaving families with tough choices to make. It might take some time to teach kids how to use phones as tools, not toys. Here are a few ways to get the message across. 

Tell them not to use phones at school. Phones can be a distraction (干扰) from learning when used in the classroom. {#blank#}1{#/blank#}In fact, 43% of teens admit that they often or sometimes use their phones as a way to avoid face-to-face communication with others. 

Encourage them to contact long-distance relatives. {#blank#}2{#/blank#} They're also for keeping in touch with people who you may not get to talk to as often. If you have families who live in another city or state, ask your kids to strike up a conversation. 

Lead by example. Setting an example is not only about how you use your phone, but also about how much you use it. When you feel bored and expect to glance over social media, fight it by taking a short walk. {#blank#}3{#/blank#}

Advise them not to use phones at the dinner table. For many families, the only time they truly get together is breaking bread at tbe end of a long day. {#blank#}4{#/blank#} Asking your children to leave their phones far from the dinner table is a great way to solve the problem. 

{#blank#}5{#/blank#} Sometimes, kids need a little push in order to make better choices about their phones. If they're struggling with healthy habits, put some real-world events on the calendar. Good options include going to an amusement park, working together on a craft project or signing your kids up for sports.

A．Plan other forms of entertainment.

B．Prepare a dinner together with your children.

C．Screen time before bed reduces sleep quality.

D．They can also prevent students from connecting with one another.

E．So it is wise of parents to stress the importance of parent child time. 

F．Also, instead of reading a headline, why not pull out a book to read?

G．Phones aren't just for texting the best friend who lives two blocks away.