Have you ever experienced the feeling of falling as you start to fall asleep? Sometimes you may come to realize this feeling. If so, don't worry. Many people have felt the same thing.

In fact, these muscle twitches (肌肉抽搐) in the arms, legs or other parts of the body are called hypnic jerks (入睡抽动) or sleep starts. And they are very common. Up to 70 percent of people experience them sometimes, Huffington Post reported. But what causes it?

There are some theories(理论). Some scientists believe that the feeling of falling comes from the body relaxing itself, especially if the person is anxious or unable to get comfortable. As you're about to sleep, your muscles become relaxed. But your brain stays awake. It misunderstands the relaxing of your muscles as a sign that you're falling. Then the brain jerks the body awake as if it's trying to protect you.

    Other scientists believe that different phases of sleep might cause the hypnic jerks. When we sleep, we experience two phases: non-rapid eye movement (NREM) and rapid eye movement (REM). During REM, our heart rate (心率), breathing and nervous system can act irregularly (不规律地). If the body experiences flashes (一瞬间) of REM while entering sleep, these irregularities could cause twitches.

If you don't want to experience hypnic jerks, scientists have some suggestions. When you become deeply relaxed, you can learn how to reconnect slowly by moving your fingers and toes a little bit. Then start to move your head and open your eyes, while being aware of yourself as you get out of the relaxed state.

    But experts agree that hypnic jerks, though sometimes scary, are harmless. If it wakes you up, simply roll over and go back to sleep. But keep in mind: a caffeinated (含咖啡因的) drink, exciting evening activities or stress may make hypnic jerks happen more often.

    Developing healthy eating habits starts from childhood, therefore it is important for parents to teach and provide children with a healthy diet.

    DPHSS administrator of the Bureau of Nutrition Services, Charlie Morris said, "A healthy diet for a child always includes a lot of fruits and vegetables in the diet limiting the amount of simple sugars in the diet and high fat food and highly processed* food." This means staying away as much as possible from food such as chips, cookies, candies and sugary drinks, because all children need to have meals and the meals should be a well-balanced diet.

    Community nutritionist* Thelma Romoso said, "The fruit, the vegetable, the grain, the protein, and also the milk, the diary product are all necessary in the diet for a child. Among them, the fruit and the vegetable should come first. It's easy for a mother to go into the two plus three concept* of fruits and vegetables or five a day." This concept means that there are at least two servings* of fruits a day, three servings of vegetables a day which can be served for lunch and dinner.

    Morris also said that the child's hunger level influences how much is eaten and the parent controls what and when the meal is offered, saying, "Mom needs to make sure that the food offered is good food for the child to eat and she also needs to consider how active they are through the day. Snacks* are not a bad thing, so the mom should offer good kinds of snacks as well."

    When it comes to preparing your child's lunch and snacks for school, make sure to keep in mind that the food you provide should not only provide enough energy but also be healthy such as fresh fruits, and whole grain bread. But parents must be sure to remember that a good healthy diet must be balanced with physical activity, that is to say, it is important that children get outside and run around and play and get activity besides eating a good diet.

Winter is the best season of the year. During the winter, months, temperatures are usually colder and there are fewer hours of daylight. The winter months in most of China are November, December, and January. 

Cold winter temperatures are caused by the tilting (倾斜) of the Earth. When Earth's Northern Hemisphere (半球) is tilted away from the sun, there are fewer hours of daylight and the temperature is colder. When the Northern Hemisphere tilts towards the sun, there is more daylight time and the temperatures are warmer. The tilting of the Earth as it spins causes the seasons to change. 

Animals have special ways of preparing themselves for winter. Some animals, like birds and butter- flies fly long distances, or migrate, to warmer places during the winter months. Other animals such as bears, gophers, snakes go to sleep through the winter. Squirrels and raccoons (浣熊) don't migrate or hibernate. Instead, they gather enough food during the fall months, so they have plenty to eat during the winter. 

In some areas, winter is a time when snow falls and gathers on the ground. People who live in these places can enjoy special winter activities like skiing or snowboarding. They can also build snow- men. When the water in lakes and rivers freeze, people can ice skate or go ice fishing!

I am John Brown. I have a happy family. There are (有) nine people in my family. They are my grandparents, my parents, my two sisters, my brother, his wife(妻子) and I. In England, it is very big.

 My grandparents are old and they like planting flowers(种花) in the garden every day. My father is a farmer and he has a farm. It is very big. My mother doesn't go to work. What does she do at home? Can you guess? Oh, she does housework. She is a housewife(家庭主妇).

 My brother is a doctor. He works in a hospital. His wife works in a hospital, too. But she is a nurse. My two sisters are students. Helen wants to be an English teacher. Her English is very good. Julia likes to sing very much. She can sing very well. So she wants to be a singer(歌手). I'm in China now. I teach English in a high school.

I have a happy and big family. I love my family very much.

①Many social media(社交媒体) articles would make you believe that everyone is happy all the time. However, being happy all the time is not possible.

②Sometimes, you might have high expectations(期望). You probably expected to get a perfect score on an exam or to be chosen for a sports team, but it didn't happen. Bad results get you down. In fact, sadness itself is not bad—it can drive you to work hard and feel better the next time.

③However, when sadness doesn't go away and you feel sad for a long time, it will influence your daily life. I remember feeling this way when my dog died. It happened on the day of my ninth birthday. I didn't want to get out of bed in the morning. I didn't want to study or go out with my friends. I was so sad that I had no courage to face the real world. I stopped doing things I enjoyed, and then isolated myself from others. I didn't get better until my family told me that my dog would have wanted me to be happy. That day, my parents and I made an agreement to live a good life.

④Depression(抑郁) is not a sign of weakness. If you sometimes feel sad, it may mean you need more attention and support. It's important to reach out to more people. When you feel down, you must not shut yourself away from the world. Instead, share your feelings with people who care you, such as your parents or your friends. Remember, you are not alone. This is a way to feel better.

Sports play a(n)1 part in our life. All over the world, people enjoy sports. Wherever you are, you can2 different kinds of sports or games. Some sports or games can go back to thousands of3 ago, like running and jumping. Chinese kung fu, for example, has a very long history.4 basketball and volleyball are new. People are inventing new sports or games all the time.

Sports help people keep healthy and happy and live5 . Lots of people take part in sports and play games. But some people like to watch6 do sports. In order to watch the games, some people7 tickets or turn on their TVs at home. They don't go to bed until the games are8 . When their favourite player gets the first or the team that they like wins, they often9 very excited.

When the seasons change, sports will change. In seasons, people play different games. For example, swimming is fun in warm weather just like in summer, but skating or skiing (滑雪) is popular in10 .