Sleep is something we all do. But some people need to sleep more than others. Babies sleep most of the time. Children in school sleep about ten to twelve hours a night. Most adults sleep only seven or eight hours. {#blank#}1{#/blank#}

    All parts of our bodies have to rest after they work.. Our arms need a rest after we lift heavy thing, When we run fast, our legs work hard. They get tired. We have to rest them. Our brains work hard, too. {#blank#}2{#/blank#}. We can sit quite still and rest our arms and legs. But our brains aren't resting. They go right on thinking as long as we are awake.

    Our brains slow down a bit when we sleep and dream. {#blank#}3{#/blank#} Instead of thinking wide-awake thoughts, our brains make up dreams. Some dreams are very pleasing. Some are not. Most of the time we forget them when we wake up.

    Scientists have tried to find out what would happen if people were not allowed to sleep. They asked some people not to go to bed. The people stayed up all night and all the next day. They stayed up the next night too, and the day after. They played games, but they made mistakes. They forgot things. {#blank#}4{#/blank#}

    The people grew rude and mean. They became angry with their friends. Finally they were too tired to stand up. When they sat down, they fell asleep.

    Scientists have found that if people are not allowed to sleep and to dream, they act in an unusual way. {#blank#}5{#/blank#} But we do know that we need it to stay well. So tonight have a good sleep. Lie down under the covers. Shut your eyes. Let your thoughts wander. Soon you'll stop thinking. You'll be asleep.

A. It was hard for their tired brains to work.

B. When we are awake, they help us pay attention to the world around us.

C. But babies, children, and adults — all of us need to have our sleep.

D. Good sleep helps to improve one's memory.

E. No one knows why sleep is so good for us.

F. But even as we sleep our brains are doing some work.

G. Of course you will have a good sleep.

    Plants are very important living things. Life could not go if there were no plants. This is because plants can make food from air, water and sunlight.{#blank#}1{#/blank#}. Animals get their food by eating plants and other animals.    So animals and man need plants in order to live.{#blank#}2{#/blank#}.

    If you look carefully at the plants around you, you will find that there are two kinds of plants: flowering plants and non-flowering plants.

    {#blank#}3{#/blank#}. The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds.{#blank#}4{#/blank#}. An example of a fruit without seeds is the banana fruit.

    {#blank#}5{#/blank#}. They grow from spores（孢子）. Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores are quite the same as the seeds, when these spores fall on wet and shady places, they usually grow into new plants.

A. There are about half a million kinds of plants in the world

B. Animals and man cannot make food from air, water and sunlight

C. But a few fruits have no seeds at all

D. Not all the plants grow from the seeds

E. This is why we find that there are so many plants around us

F. Flowering plants can make seeds

G. Most non-flowering plants don't grow from seeds

    Sticking to a vegan（纯素食的）diet might sound difficult. {#blank#}1{#/blank#} According to Huffpost, more than 3 million people in the US are vegans. And in the UK, about 542,000 people turned vegan during the last decade.

    {#blank#}2{#/blank#}

    One reason could be that people want to reduce greenhouse gas emissions（排放）. {#blank#}3{#/blank#} In fact, it's believed to account for 18 percent of the world's greenhouse gas emissions, according to a 2013 study by the UN Food and Agriculture Organization. This amount is even greater than that of all the world's cars, trains and planes combined.

    A growing number of people are also starting to believe that it's wrong to kill animals for food. Therefore, some of them made an ethical（道德的）choice to become vegan.

    {#blank#}4{#/blank#}Vegan celebrities often use social media to spread the message of veganism and share tips on how to live a vegan lifestyle.

    But experts also want to remind people that meat is important for our health. {#blank#}5{#/blank#} So, if you're thinking about becoming vegan, you should do some research before making your decision.

A. Meat production is very bad for the environment.

B. So why exactly has veganism become so popular?

C. It is up to you to decide whether to go vegan or not.

D. Social media is also believed to be behind the increase in veganism.

E. Fresh fruits and vegetables, grains and nuts are all key to a vegan diet.

F. But in recent years, veganism has become a popular lifestyle in many places.

G. They say that a strict vegan diet may not offer everything that the human body needs.

    Who would win in a competition to memorize numbers, a chimp or a teenager? The teenager? Think again. Scientists have proved that chimps perform better than human beings when it comes to this kind of problem.

    {#blank#}1{#/blank#}.

    Memory is our ability to learn something, save it and recall it when needed. Our memories are important to our sense of self, our personalities, and our ability to understand the world.

    {#blank#}2{#/blank#} There is short-term memory and long-term memory. Your short-term memory saves information for a few seconds or a few minutes. {#blank#}3{#/blank#} Long-term memory involves the information you try hard to keep, because it's meaningful to you-an example is data about family and friends. And then there is visual memory and sound memory. But these are not hard and fast. In fact, Scientists argue a lot about the nature of memory.

    {#blank#}4{#/blank#} Some memorize better with the help of pictures. Others are helped more by sounds. One thing's for sure though: If you can put the different kinds of memory together, there can be great results. {#blank#}5{#/blank#} At the same time, you could listen to recordings of the same group of words. These things may help when it comes to memorizing the words.

    Imagination and association can be useful too. By imagination, scientists mean picturing a word in your mind, while association means relating the word to something you already know.

A. So why not try pictures with English words?

B. Then how do chimps have better memories than us?

C. Scientists say that there are different types of memory.

D. We may have to rethink what we believe about human memory.

E. Scientists have also found that people memorize things in different ways.

F. For example, the time it takes to compare the prices of a few items in a store.

G. Short-term and long-term memory differ in the amount of information they can store.

    While it is impossible to live completely free of stress, it is possible to prevent stress as well as reduce its effect when it can't be avoided. {#blank#}1{#/blank#}

    Try physical activity.

    {#blank#}2{#/blank#} Running, walking, playing tennis, and working in your garden are just some of the activities you might try.

    Make time for yourself.

    Arrange time for both work and fun. Don't forget, play can be just as important as your overall well-being as work. {#blank#}3{#/blank#} Go window-shopping or work on a hobby. Allow yourself at least a half hour each day to do something you enjoy.

    Take care of yourself.

    {#blank#}4{#/blank#}If you easily get angry and can't sleep well enough, or if you're not eating properly, it will be more likely that you will fall into stressful situations. If stress repeatedly keeps you from sleeping, you should go to see a doctor.

    {#blank#}5{#/blank#}

    Stress can result from disorganization and a feeling that "there's so much to do, not enough time". Trying to take care of everything at once can be too much for you and as a result, you may not achieve anything. Instead, make a list of everything you have to do, than do one thing at a time, checking off each task as it is completed. Set out to do the most important task first.

A. Make a list of things to do.

B. Do whatever you like and want to do.

C. You could smile to yourself in front of a mirror every day.

D. The following are suggestions for ways to deal with stress.

E. You should make every effort to eat well and get enough rest.

F. You need a break from your daily routine to just relax and have fun.

G. When you are nervous, angry or upset, try reducing the pressure through exercise or physical activity.

Choose a friend who is honest. A friend that is honest is one of the best friends you can have. An honest friend will keep you from walking out of the house wearing that awful green shirt. They're supportive in their honesty. {#blank#}1{#/blank#}.

Choose a friend who stands by you in the hard times. {#blank#}2{#/blank#} There are all kinds of laughter and joyful moments, and those times make relationships easy. But who are the people that stand by you when times turn hard? Those are your true friends.

Choose a friend who gives as much as he or she takes. We've all had friends that only want things from us. {#blank#}3{#/blank#}When a relationship is one-sided, we just end up feeling angry. It's not healthy. Choose a friend with whom you feel a balance of give and take.

Choose a friend who likes the things you do. While friendship is full of compromise (妥协)，it helps if you choose friends who share a lot of your interests. {#blank#}4{#/blank#} It makes deciding on things to do easier. You don't have to choose a friend who likes every single little thing you do, but you should have some shared interests.

{#blank#}5{#/blank#}Friends need to laugh together. Choose a friend who can laugh with you rather than at you. Look for someone who will laugh with you at a look or a glance. Those people will be some of your best friends.

A. In some ways, they are family.

B. Choose a friend who gets your faith.

C. It gives you things to talk about or share.

D. Choose a friend who gets your sense of humour.

E. And you should choose someone that will not lie.

F. It's easy for us to be good friends in the fun times.

G. But they never seem willing to give anything to us when we need it.