Miss Kate taught physics in a New York school. Last month she was explaining to one of her classes about sound, and she decided to test them to see how well they had understood her explanation. She said to them, "Now, I have a brother in Los Angeles. If I was calling him on the phone, and at the same time you were 80 meters away, and were listening to me from across the street, which of you would hear what I said earlier, my brother or you and for what reason?"

A boy at once answered, " Your brother, Miss Kate, because electricity travels faster than sound waves(声波).

"That's very good." Miss Kate said, but then Jenny said, "I don't agree. Your brother would hear you earlier because it is 11 o'clock here, it's only eight o'clock in Los Angeles."

B

    It is important for each child to get enough sleep every day．Here．we'll learn more about that．{#blank#}1{#/blank#}

    It usually depends on their age．Newborns (新生儿)of 0 to 3 months should sleep for about 18 hours a day．Babies of 4 to 11 months should start to sleep through the night，for 9 to 12 hours at a time．{#blank#}2{#/blank#}Children of 3 to 5 years should get 11 to 13 hours a day．Children of 6 to 13 need 9 to 11 hours of sleep．Teenagers of 14 and up need 8 to 10 hours of sleep．{#blank#}3{#/blank#}

    Set a strict nap timetable(小睡时间表)．Younger children should take a short sleep during the day．Even older children can benefit(得益于)from late—afternoon naps if they don't get enough steep at night．{#blank#}4{#/blank#}

    Pay attention to(注意)screen time．Remember to ask children to tum off the television and the computer an hour before they go to bed．If possible，get them out of their bedrooms since the light(光)from the screens can make sleep a difficult job．

Get children movin9．{#blank#}5{#/blank#}Running around and playing sports are great, but children can move in other ways．too．They can take a dog for a walk or go to the park—just get them out of the house and get them moving．

    It may take a long time for some people to learn to speak English. However, by following these tips（实用的提示） you should be speaking English in no time.

    Tip I: Forget about having a large vocabulary. Only learn the words you will need most. For example, if you are traveling in an English-speaking country, make a list of all the possible sentences and questions that you would need to know, such as "Do you know where the nearest bathroom is? "and" I am lost. Can you help me?" Think about what sentences you would want a traveler to know if they came to your country and couldn't speak your language.

    Tip 2: Once you have a list of vocabulary that you think will be most useful to you, make sure you understand the meaning of each word and know how to use each word in a sentence. Try making lists with new words and sample sentences(例句). Ten new words is enough on each list. Then stick(粘贴)the lists up all over your house where you can easily see them. Practice every day. Whenever you see a list, make sure you stop and read through it.

    Tip 3: Now pronounce these words and sentences properly. Try to learn pronunciation by listening to how English speakers pronounce words. Watch English TV shows, listen to English radio programs and try to talk with as many English speakers as you can, online or in person.

    I wish you the best of luck and I hope my tips are helpful!

    You are invited to a large party. Loud music is playing, and lots of people are dancing. Do you dance or talk to as many people as you can all night? Later, you cannot fall asleep-you want more conversation! Or do you prefer a quieter corner? Or perhaps you cannot wait to go home early and relax by yourself.

    Which of these people sound most like you? Person A, who tries to talk to everyone and stays late? Or Person B, who prefers to keep quiet and leaves early?

    If you said Person A, you are probably more extroverted(性格外向的) . If you said Person B. you are probably more introverted(内向的), Or perhaps you are Person C and fall somewhere in the middle. Introverted and extroverted are two commonly used words to describe a person's personality. And they are also commonly misused and misunderstood.

    Introverts may be thought as quiet, shy and timid. Extroverts may be thought as bold, confident, loud and full of energy. Introverted and extroverted people may fit those descriptions, But these same descriptions do not define(下定义) introversion and extroversion properly.

    Introverts and extroverts use their brains differently, and they get their energy differently. Introversion is the state of being mostly concerned with one's own mental life. Extroversion is the opposite. Extroversion is the state of being mostly concerned with what is outside oneself.

    People who consider themselves introverts may say they "need to be alone to charge their batteries". However, introverts may still love being social and going to parties. But such activities require time to prepare.

    Extroverts may say, "I don't need 'alone time'. 1 feel more relaxed being around other people. "Even so, extroverts can still feel unsure or not confident among other people.

    So where do you fall on the introversion/extroversion chart?