In the universe, as we all know, there is the sun, the moon, the earth and a good many stars. Through our geography lessons, we know the earth goes around the sun, and the moon goes around the earth. We have day and night because the earth keeps turning all the time. When our part of the earth turns to the sun, it is day. When our part of the earth turns away from the sun, it is night.

Just because the moon is closer to the earth than the sun, it looks much bigger than the sun. Big things will look smaller when they are further, and small things also look bigger when they are nearer.

    The sun is big enough to give out very strong light. The moon can't give any light at all, but it looks quite bright, too. Why? In fact, the light from the moon comes from the sun. The moon looks much bigger and brighter than the stars. But actually (事实上) the stars are much bigger and brighter than the moon. They look smaller than the moon also because they are further away from the earth.

    There are many other planets in the universe. But of all the planets, only on the earth there are living things and people can only live on the earth, too. But at 9:00 a.m. on October 15th，2003, Chinese pilot Yang Liwei was sent up to space. He stayed there for 21 hours. It was the first time for Chinese to get into space.

    As we know, all living things have to eat food. For a man, a tiger, a fish, a bird, or even a worm, food is needed. We know all living things are sure to die without food. In every part of the world, different kinds of animals share living places and live in communities (群落) together. They are connected(联系) in a food chain.

    In a food chain, some living things are producers and some are consumers. Plants are producers because they use sunlight, soil and other things to make their own food. Animals are consumers because they have to eat other animals or plants.

    There are four different kinds of consumers in the animal world. A carnivore is an animal that only eats other animals. An herbivore is an animal that only eats plants. An omnivore is an animal that eats plants and animals. A scavenger is an animal that eats dead animal.

    Here is a picture of a food chain. The food chain shows how animal eat each other in a community. In the picture, you can see what animal or plant is food for another animal. See? The grass is food for a rabbit(兔子), which then becomes food for a hungry tiger. In this way, all of these animals are connected.

    We often find that weekends and holidays feel so short while classes and work feel so long. Actually, though, we know that this is not true. But we still wonder where that strange feeling comes from.

    In fact, this is one of the ways that we're tricked by time, according to the website. All that S interesting. The website lists several wrong impressions (印象) we often have about time. Let's have a look.

    First of all, emotions affect (影响) our time-keeping abilities. Negative emotions (消极情绪). especially anxiety and boredom, make time seem longer because they make us concentrate (集中) more on the passage of time. However, when we are enjoying ourselves, we pay more attention to what we are doing and are likely to lose track of (失去对……的意识) time.

    Here is another example. In 2007, a group of scientists carried out a test. In the test, people fell 50 meters into a safety net and were then asked about their experience. Although the experience took shorter than 3 seconds, the people thought it was much longer than it actually was.

    This is because of the way our bodies reply to danger, according to the scientists. Our bodies produce a chemical called adrenaline (肾上腺素) when we are faced with danger. It allows us to concentrate better so that we can stay alive. As a result, we are able to remember far more details (细节) over a short period of time, which makes it seem like time is going more slowly.

    Another situation when we make mistakes about time is when we take afternoon naps (午觉). Have you ever had trouble telling what time it is after a long nap? That's because the best amount of time for a nap is 20 minutes. After 20 minutes, you enter a new stage of sleep called slow-wave sleep. If you wake up mid-way in this stage, it will take a while before you can correctly perceive (感知) time again.

    Yes, time can be mysterious (神秘的) and there is no way to control it. So, perhaps the best thing to do is to make good use of every minute.

{#blank#}1{#/blank#}: their family names, given names and courtesy names (字)

Take the famous poet Li Bai as an example. His family name was Li, his given name was Bai. {#blank#}2{#/blank#}

People used their given names when they were among family members. But in social life, they called each other by their courtesy names to show respect. {#blank#}3{#/blank#} If you were talking about yourself, or if your elders were talking about you, the given name would be used instead of the courtesy name. 

Men would get their courtesy names when they turned 20. It was a symbol of adulthood(成人). {#blank#}4{#/blank#}

{#blank#}5{#/blank#} For example, Mencius' name was Meng Ke (孟). His courtesy name was Ziyu (子舆). Both Ke and Ziyu mean "carriage(马车)". Zhuge Liang's given name was Liang, which means "bright". His courtesy name was Kongming, which means "very bright". 

On the morning of every Monday, two of my children get ready for school. They each carry a large bag with some clothes, a pair of shoes, lots of food and water. But there isn't any book in it. Then instead of walking them to school as I do on the other school days, I drive them to a nearby park. This is where they are going to spend (度过) the day and have lessons. Right, my boys go to a forest school once a week. It is from 8:30 a. m. to 3 :30 p. m. A group of kids explore (探索) the forests, lakes and animals in nature together. 

I love the idea of the forest school, but I worry about a few things at first. Would the teachers be nice? Would my kids have fun?

The fact is that my boys get used to (习惯于) the school life quickly. Most of the time, they plan their own play, climb tall trees, build fires and do many other interesting things. The teachers never tell them that their play is too high, too fast, or too dangerous. They only follow the kids and help when something goes wrong. 

When I pick the boys up at the end of the afternoon, they often look lively, happy and never want to leave. The forest school teaches them to look after themselves and get along well with nature. I think that is important.