Parents often believe that they have a good relationship with their teenagers. But last summer, Joanna Henry noticed a change in their older son: suddenly he seemed to be talking far more to his friends than to his parents. “The door of his room is always closed,” Joanna noted.

    Tina and Mark noticed similar changes in their 14-year-old daughter. “She used to cuddle up (蜷伏) with me on the sofa and talk,” said Mark. “Now we joke that she does this only when she wants something. Sometimes she wants to be treated like a little girl and sometimes like a young lady. The problem is to find out which time is which.”

Before age 11, children like to tell their parents what's on their minds. “In fact, parents are first on the list,” said Michael Riera, writer of Uncommon Sense for Parents with Teenagers. “This completely changes during the teen years.” Riera explained. “They talk to their friends first, then maybe their teachers，and their parents last.”

Parents who know what's going on in their teenagers' lives are in the best position to help them. To break down the wall of silence, parents should create chances to understand what their children want to say, and try to find ways to talk and write to them. And they must give their children a mental (精神的) break, for children also need freedom, though young. Another thing parents should remember is that to be a friend, not a manager(管理者), with their children is a better way to know them.

    Babies born after 2017 may never need to take a driving lesson because of the development of self ­driving cars. Some scientists say that self ­driving or driverless cars(无人驾驶汽车)may hit the roads within 15 years, and it is possible that driving may become unnecessary, or more relaxing and enjoyable.

    Companies like Google, Baidu, Apple and Alibaba are working on driverless cars. But, if the tests are successful, these electric self­ driving cars could be put into use very soon. This kind of cars may change the way we live in the future. All you have to do is to type in the address!

    According to Baidu, driverless technology has the following four advantages. Firstly, driverless cars are actually safer. With driverless cars, the number of deaths caused by accidents will decrease. Secondly, driverless cars are more efficient(效率高的) than manned cars. Thirdly, driverless cars follow the traffic rules. Therefore traffic control will be easier to achieve. At last, the cost of transportation will be reduced as the labor cost becomes less.

    There are many different technologies needed to make a successful self ­driving car. The most difficult technologies of all are environmental perception(感知), behavior prediction, planning control, HD mapping, and exact GPS.

    My mother used to ask me what the most important part of the body was. I got different answers at different ages.

    When I was young, I thought sound was very important to us, so I said, "My ears, Mum. "But she shook her head and said no. Several years passed, and she asked me again. I believed that I got the right answer after thinking it over. So I told her，"Sight is very important to everyone, so it must be our eyes. "But she told me I was wrong. I tried many times after that, but her answer was always the same. Till last year, my grandma died. Everybody was crying, and everybody was hurt. My mom looked at me and asked me with tears in her eyes，"Do you know the answer now？"I was surprised when she asked me this question then. "My son, the answer is your shoulder. Everyone needs a shoulder to cry on. "

    Finally, I realized (意识到)all she hoped is that I can have enough love and friends so that I will have a shoulder to cry on when I need it.

    We all know that many inventions have changed our life a lot. They play important roles in our daily life. Here are some interesting inventions.

    All week long, it seems you sit inside at school when it is fine outside. But when the weekend comes, it is very cloudy. There is rain according to(根据) the weather report.

    Scientists studied more than 40 years of weather data(数据) from around the world. It shows weekend weather is different from weekday weather in some places.

    Part of the study involved(包括) 660 weather stations in the US. At more than 230 of these places, the weather on Saturday, Sunday and Monday was different from the weather on Wednesday, Thursday and Friday. The difference was small, but the pattern was striking enough to make the scientists take notice.

    "This kind of weekly rise and fall doesn't line up with any natural cycles, "the scientists say. Instead, they think that air pollution from human activities makes the weather become different.

    What do you see when you look at abstract (抽象的)art? Can you understand it? Does it look like anything?

    Abstract art became popular in the early 20th century. Artists did not want to paint, draw, or sculpt things exactly like they looked. They didn't want their art to be realistic(现实的). They were more interested in basic shapes and colours.

    Picasso is probably the most famous of these artists. He painted and drew in many, many styles. Sometimes he used a lot of blue colours (his "blue period"). Later, he used more red and pink colours (his "rose period"). Many of his other paintings are called "cubist (立体派的)" because they are made of painted squares.

    After a long time, Picasso's paintings became more and more abstract. He painted people and things using strange shapes. His work was so strange that many of his workmates didn't understand it.

    Kandinsky, another famous artist, used lines, shapes, and patterns to paint his subjects. His paintings also used strong colours to express feelings. Other artists like the surrealists (超现实主义画家)，were interested in subconsciousness (潜意识). Painters like Breton and Magritte used many symbols in their work. The meaning or subject of their work wasn't always clear. Dali, another surrealist artist, painted pictures that looked like dreams.

    There are still many abstract artists around the world. That's the way many artists prefer. They want each person to look at art and find their own meaning in it.