Why do parents have such a difficult time to communicate openly and honestly with their teens? For this, there are many reasons but most of them stem from not being able to properly understand their teens. It is a dangerous gap because parents will have to communicate with their teens about a wide variety of issues during the most important years of their lives. Thus, parents must know how to communicate openly and honestly with their teens.

    Here are a few tips to make communication easier between parents and teenagers.

    1）Try not to talk down to your teens. Make them feel as if their views really matter, which not only helps your discussions with your teen but bring you closer to him.

    2）Imagine what it would be like to be a teen. Try to remember some of the negative feelings you experienced as a teenager and apply it to your teen's situation.

    3）Never make negative remarks to your teen about what he has said or done.

    4）Remember how much courage it would have taken for your teen to come and talk to you about his personal issues. So listen respectfully.

    5）Don't ignore your teen's feelings because it is usually a cry for help. For instance, if your teen is unusually angry, it may be time to spend a bit of quality time with your teen to determine what is wrong and where he is coming from.

    It is, therefore, necessary for parents to strive to keep lines of communication open at all times with their teens. Try to remember what it was like to be a teenager and how vulnerable（脆弱的）you felt. Then you will be well on your way to help your teen communicate more openly and honestly.

    Recently some American scientists have given a useful piece of advice to people in industrialized nations．They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago． {#blank#}1{#/blank#}

    The scientists say that the human life has changed greatly．Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sicknesses． {#blank#}2{#/blank#} So they are called “diseases of civilization”．Many cancers and diseases of the blood system are examples of such diseases.

    Scientists noted that people in both the Old Stone Age and the New Stone Age enjoyed very little alcohol or tobacco, probably none． {#blank#}3{#/blank#} However, a change in food is one of the main differences between life in ancient times and that of today.

    Stone Age people hunted wild animals for their meat, which had much less fat than domestic ones．They ate a lot of fresh wild vegetables and fruits．They did not have milk or any other dairy products, and they made very little use of grains． {#blank#}4{#/blank#} We eat six times more salt than our ancestors．We eat more sugar．We eat twice as much fat but only one third as much protein and much less vitamin C.

    {#blank#}5{#/blank#} But scientists say that we would be much healthier if we eat much the same way the ancient people did, cutting the amount of fatty, salty and sweet food.

A．Stone Age people lived a simple life.

B．But today, we enjoy eating a lot of these.

C．In that case, they would live much healthier.

D．Ancient people also got lots of physical exercise.

E．These new sicknesses were not known in ancient times.

F．People today probably don't want to live like our ancestors.

G．Modern people used to suffer from “diseases of civilization”.

    Growing up in one of the poorest communities with most crimes in Los Angeles, US, being raised by a poorly-educated single mother and attending the worst-quality public school, not many people expected much of me, so I chose to expect something of myself.

    On my 12th birthday, I bought a poster of Harvard University to hang in my room. Being at Harvard became my dream: I saw myself attending class in Sanders Theater, studying in Widener Library and eating in Annenberg Hall. Driven by this dream, I kept studying hard. I'd begin my day by asking myself these two questions: “What do I want in my life?” and “Are the things I am doing today going to get me closer to that life?”

    Asking myself the questions gave me the courage to ask over 50 Harvard, students for advice on my application essays; it gave me the energy to study just one more hour on my SATs when others were asleep; and it gave me the determination to apply for just one more scholarship when already refused many times. Moreover, reminding myself of my goal each day made it easy to say no to the same choices my friends made, because they would never get me closer to my goal. I found that even being poor could not take away my power to decide what I choose to do with my life.

    Every day I could feel myself getting closer and closer to my goal as my writing got better, my SAT score increased, and my scholarship offers started coming in. On March 31st, 2011, an email arrived from Harvard. The first word was “Congratulations!”. Tears of joy filled my eyes.

    Who you are today is the result of the decisions you made yesterday, and who you will be tomorrow will be the result of the choices you make today. Who do you want to be tomorrow?

    Artificial intelligence keeps defeating human, it is making countless victories against human in different fields of life and trying to push human to the corner.

    Google's DeepMind has defeated the world's number one player Ke Jie. Human brain somehow has been replaced by a machine and scientists are working very hard on developing a human brain by implanting a chip and connecting it to the thick neuron that connects the two hemispheres of the brain. Well, who doesn't want to get his brain upgraded to be as smart as the brain of Albert Einstein or Charles Darwin?

    Humans will probably one day invent a brain that can be implanted in the human skull and reprogram all the human thoughts, but this invention doesn't seems to be happening in the foreseeable future since human brain took millions of years to evolve. Some scientists believe that human will defeat death in the next twenty hundred years but they can't really predict how long it's going to take to develop a human brain that can completely replace the natural brain.

    Despite of this accomplishment in the field of artificial intelligence, it couldn't crease people from believing that science can't stand alone. For instance, AI can imitate human brain and most of the time outperforms it, but there are still a lot of hidden secrets. AI outsmarted Ke Jie has consciousness unlike the AI, Ke Jie felt sad when he was defeated and buried his face in his hands but the AI didn't feel happy and celebrate his victory.

    The computer of 1960 is the same as the computer of 2017 in terms of consciousness, there is no signs so far telling us that there is an algorithm(运算)that can make a conscious computer and decipher (译解) its feelings. We can predict what the future will look like according to the past, especially from scientific point of view but the development of human brain seems unpredictable and unknown.

    Siri, whose voice do you have?

    The question has interested millions of Apple iPhone and iPad fans, who use the devices' Siri function for help with everything from finding restaurants and directions to organize their day.

    On Friday, CNN reported it had discovered the original voice. The person had never before been identified publicly.

    The network named Susan Bennett, a voice-over actress（配音演员）from Atlanta in the US, as the voice behind Siri, which was first introduced on Apple's iPhone 4s in 2011.

    "I'm the voice actor who provided the voice of Siri," Bennett told CNN in an interview.

    Bennett told the network she worked four hours a day for the entire month of July 2005 recording in her home. She said she was paid by the hour but would not reveal the amount.

    "A colleague emailed me and said, 'Hey, we've been playing around with this new Apple phone. Isn't this you?'" Bennett told CNN.

    Her voice may also be familiar to airline passengers who have passed through a Delta Airlines terminal.

    Bennett also provided the radio and TV voice of First National Bank's "Tillie the All-Time Teller", the first ATM machine, she told CNN.

    "I began my career as a machine many years ago," Bennett told the network. "I'm sure that you hear my voice at some point every day."

Concrete has served as the foundation stone of the construction industry for hundreds of years. However, the process of producing concrete is one of the most environmentally unfriendly processes in the world. In the process, not only is carbon dioxide（二氧化碳）released into the air by the energy used to heat the limestone, but the limestone itself also gives out a huge amount of the element. 

Luckily, a number of start-ups throughout the world are using creative thinking to make the construction industry a whole lot more friendly for the planet. 

A Canadian company called CarbonCure, has found a way to inject（注入）concrete with carbon dioxide itself. Not only does this trap the carbon dioxide into the concrete, keeping it from running away into the atmosphere, but it also creates a super strong material called calcium carbonate, which reduces the total amount of concrete that needs to be used. 

California-based Brimstone, is creating carbon-negative concrete by doing away with limestone entirely and instead using silicate rock, a material that does not release carbon dioxide when heated. Instead, the process produces magnesium（镁）, which absorbs carbon dioxide, as the basis for their concrete. 

Additionally, researchers at Australia's RMIT University have recently released a study showing that adding coffee grounds instead of sand to concrete could make it much stronger, reducing both the amount of sand used, as well as the amount of concrete that would need to be used in the final product. 

The biggest barrier at this point is convincing members of the industry that the new types of concrete are safe to be used, according to Stacy Smedley, director at a nonprofit focused on decarbonizing construction. 

Hopefully these new solutions to the environmental problems of concrete will soon be widely adopted. Given the significant part the construction industry has in releasing carbon dioxide into the atmosphere, great improvements can be made when more environmentally-friendly materials are used.