Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren't very smooth rub together to make heat energy. The faster you rub two things together, the more friction (and heat) you can make. Let's discover friction!

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    Almost all cultures celebrate the end of one year and the beginning of another in some way. Different cultures celebrate the beginning of a new year in different ways, and at different times on the calendar(日历).

    In Western countries, people usually celebrate New Year at midnight on December 31st—January 1st. People may go to parties, sometimes dressed in formal(正式的) clothes, and they may drink champagne(香槟酒)at midnight. During the first minutes of the new year, people cheer and wish each other happiness for the year ahead. But some cultures prefer to celebrate the new year by waking up early to watch the sunrise. They welcome the new year with the first light of the sunrise.

    Many cultures also do special things to get rid of(摆脱) bad luck at the beginning of a new year. For example, in Ecuador(厄瓜多尔), families make a big doll from old clothes. The doll is filled with old newspapers and firecrackers. At midnight, these dolls are burned(燃烧) to show the bad things from the past year are gone and the new year can start afresh(重新). Other common traditions to keep away bad luck in a new year include throwing things into rivers or the ocean, or saying special things on the first day of the new year.

    Other New Year traditions are followed to bring good luck in the new year. One widespread(普遍的) Spanish tradition for good luck is to eat grapes on New Year's Day. The more grapes a person eats, the more good luck the person will have in the year. In France, people eat pancakes for good luck at New Year. In the United States, some people eat black­ eyed peas(豌豆) for good luck—but to get good luck for a whole year you have to eat 365 of them!

    Sometimes it seems that time is flying. Perhaps it doesn't need to feel this way. Our experience of time can be possibly changed. By understanding the psychological (心理学的) processes behind our different experiences of time, we might be able to slow down time a little.

    One basic law of psychological time is that time seems to slow down when we're exposed (接触) to new environments and experiences. The law is caused by the relationship between our experience of time and the amount of information our minds process. The more information our minds take in, the slower time seems to pass.

    It follows, then, that we have different experiences of time in different situations. In some situations, our life is full of new experiences. Our minds process a lot of information and time seems to slow down. In other situations, we have fewer new experiences and the world around us becomes more and more familiar (熟悉的). We become insensitive to our experience, which means we process less information, and time seems to speed up.

    How can we slow down time? Here are two suggestions.

    Firstly, since we know that familiarity makes time pass faster, we can expose ourselves to as many new experiences as possible. We can give ourselves new challenges, meet new people, and expose our minds to new information, hobbies and skills. This will increase the amount of information our minds process and expand (增加) our experience of time.

    Secondly, and perhaps most effectively, we can give our whole attention to an experience-to what we are seeing, feeling, tasting, smelling or hearing. This means living through our senses rather than through our thoughts. For example, on the way home, focus your attention outside of yourself, instead of thinking about the problems you have to deal with. Look at the sky, or at the buildings you pass, traveling among them. This open attitude to your experiences helps take in more information and also has a time-expanding effect.

    To a certain degree, we can understand and control our experience of time passing. It's possible for us to slow down time by expanding our experience of time.

    Beautysleep is a real thing, researches have shown that people who have enough sleeplook more attractive (有魅力的) to others.

    A few badnights are enough to make a person look especially "more ugly", theirsleep experiments show.

    Theresearchers asked 25 university students to join in their sleep experiment.They were asked to get a good night's sleep for two nights.

    A weeklater, they were asked to sleep for only four hour every night for two nightsin a row. The researchers took make—up free (素颜) photos of the volunteers afterboth the good and the bad sleep.

    Next, theyasked 122 strangers to have a look at the photos and judge (评价) them on attractiveness, health,and sleepiness, as well as asking them: "How much would you like to makefriends with this person in the picture?"

    Thestrangers were good at judging whether the person they were looking at wastired, and if he was sleepy, his attractiveness score would be low.

    Thestrangers also said they wouldn't want tosocialize with the tiredstudents. The researchers say this is natural for people. An unhealthy-lookingface makes people run away. In other words, people don't want to hang aroundwith people who might be ill.

    Dr Brewer,an expert at the University of Liverpool said: "Judgment of attractivenessis often unconscious (无意识的), but we all do it, and we are able to judge on even somethingsmall like whether someone looks tired or unhealthy. This study is a goodreminder of how important sleep is to us."

This is a new school in Shenzhen, Guangdong. There are 55 classes from Grade One to Grade Nine. It is big. In this school, the students can sleep in their classroom at noon.

After lunch, students put all the desks and chairs in the middle of the classroom. Then they get beds out of the drawers（抽屉）. At last, all the students find their beds to sleep. After five minutes, the classroom turns into a special（特殊的）bedroom! "It is good to have a rest in the classroom!" said Liu Mingming, a student of Grade Six.

The head teacher Luo Can got the good the idea of the drawer bed. "It can help students learn better in the afternoon.", she said.

"The idea is so great. Good school and good head teacher!" said Chen Hong, one of the parents in the school.

Balancing(平衡) your diet(饮食) is important. {#blank#}1{#/blank#}Let me tell you.

{#blank#}2{#/blank#}If you don't have time to sit down and have a healthy breakfast, try vegetable juice before you go to school. This is better than coffee.

Eat less salt. {#blank#}3{#/blank#}So eat less or give them up. Stay away from foods with too much fat. You can eat vegetables, fruits, fish and chicken. {#blank#}4{#/blank#}For example, you can eat

chicken hamburgers instead of(而不是) beef hamburgers.

{#blank#}5{#/blank#}You can let your mother make lunch at home and take it to school. Eat some cabbage or salads with chicken. Also, drink lots of water every day.