The wonderful experiment I am going to introduce proves that air is just all around and that it presses down upon us. Air pressure is a wonderful force. When you swim underwater, you can feel water push down your body. The air all around you does the same. However, your body is so used to it that you do not notice this. The pressure is caused by a layer of air called the atmosphere. This layer surrounds the Earth, extending to about five kilometers above the Earth’s surface.
The following experiment is an easy one that you can do at home. But make sure that you are supervised, because you will need to use matches. Now for the experiment!
What you need:
·A hard-boiled egg without the shell
·A bottle with a neck slightly smaller than the egg
·A piece of paper
·A match
Method:
1) Check that the paper will sit firmly on the neck of the bottle.
2) Tear the paper into strips and put the strips into the bottle.
3) Light the paper by dropping a burning match into the bottle.
4)Quickly sit the egg on the neck of the bottle.
Result:
Astonishingly, the egg will be sucked into the bottle. Your friends will be amazed when you show them the experiment. But be careful when you handle matches.
Why it happened
As the paper burns, it needs oxygen and uses up the oxygen(air)in the bottle. The egg acts as a seal in the neck of the bottle, so no more air can get inside. This reduces the air pressure inside the bottle. The air pressure must equalize, so more air from outside must enter the bottle. The outside air pressure against the egg and then the egg is pushed into the bottle! This proves that air is all around and that it is pressing down on it.
1. Why is there the need to take care when you are doing the experiment?A.The bottle could break. |
B.You need to light the paper with a match. |
C.The egg needs to be shelled. |
D.The egg has to be perfectly placed on the neck of the bottle. |
A.equalize the air pressure inside and outside |
B.make a seal in the neck of the bottle |
C.finish up the oxygen inside the bottle |
D.produce more oxygen inside the bottle |
A.The oxygen inside the bottle sucked the egg in. |
B.It became salt without the shell. |
C.The neck of the bottle was wide enough. |
D.The outside air pressure forced it into the bottle. |
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【推荐1】Downloading files is one of the primary uses of the Internet. You can find virtually anything online, and chances are that you've been downloading files ever since you started using your computer. Your Operating System will attempt to put all of your downloads in one central location, but eventually you may have downloaded files all over your computer. Knowing how to quickly find your downloaded files can save you a lot of time and headache.
● Check your Downloads folder(文件夹). Windows includes a Downloads folder that acts as the default (默认的) download location for most programs for every user. There are a couple of ways you may be able to find your Downloads folder:
Click the Start menu and then click your user name. You should see a Downloads folder in the window that opens.
Open Windows Explorer ⊞ Win+E. Your Downloads folder may be listed in the left frame under "Favorites" or "Computer/This PC".
Press ⊞ Win+R and type shell: downloads. Press ↵ Enter to open the Downloads folder.
● Check other locations. If you download with a lot of programs, chances are that your downloads have become a bit spread out. Other popular places for your downloads to appear are your Desktop and your Documents/My Documents folder.
If you have a secondary drive that acts as a file storage, check to see if you've created a download folder on it as well.
● Search for the file. If you know the name of the file you downloaded, you can search for it to quickly open it. Press ⊞ Win and start typing the name of the file. You should see it appear in the search results.
● Open your downloaded files. You shouldn't have much difficulty opening most files that you download online, but you may run across a few file types that can give you problems. See the guides below for details on opening these troublesome files.
Playing MKV video files
……
1. This passage aims to instruct Internet users _____.A.how to download files from the Internet |
B.how to search for files on the Internet |
C.how to find files downloaded from the Internet |
D.how to open the folders on the Internet |
A.press ⊞ Win+R | B.click My Documents |
C.extract an RAR file | D.open the Downloads folder. |
【推荐2】Drawing For Fun
You will learn some basic techniques using soft pencils. These and different types of paper are provided. Just bring yourself and a willingness to ''have a go''. This is a start-up day so people who have already attended courses should not apply.
Time: 1:00 PM-3:00 PM
Focus On Landscapes
This course is designed for students who are familiar with painting in watercolours, but are having difficulty with some techniques. We will discuss choice of materials, colour mixing and other areas that may be raised.
The day will start with a demonstration, followed by a chance to paint outdoors. After a light lunch cooked in the studio, there will be a further practice session.
Time: 9:30 AM-3:00 PM
Find Your Voice
You may feel you can’t sing or you may be a good singer who wants to develop singing skills. You will be shown how to sing correctly and how to project your voice. You may atend this course more than once and each time you will have a wonderful experience. Everyone can sing and it's great fun.
Time: 2:00 PM-5:00 PM
The Music Takeaway
Get some friends, family or coworkers together for your own music course in a place of your choice, which could be your front room, basement or workplace. We send two guitar teachers to lead a one-day course for you in the sty le of music you prefer, such as rock, country, funk or blues.
Time: 2:30 PM-9:00 PM
1. Those who attend Drawing For Fun are required to_____________.A.bring their own works |
B.be a newcomer to the course |
C.be good at watercolour painting |
D.bring their own pencils and paper |
A.Paint outdoors. |
B.Discuss the painting materials. |
C.Improve the students painting techniques. |
D.Teach how to start watercolour-painting. |
A.Find Your Voice. |
B.Drawing For Fun. |
C.Focus On Landscapes. |
D.The Music Takeaway. |
A.Find your Voice. | B.Drawing For Fun. |
C.The Music Takeaway. | D.Focus On Landscapes. |
A.All last a whole day. | B.All offer free lunch. |
C.All are related to the arts. | D.All are open to all levels. |
【推荐3】Nanny Poppinz
If you find yourself in need of a babysitter (保姆), the Internet is a great place to start. And in truth, it can be a great way to find someone to care for your child if you know where to look, what questions to ask, and how to examine the babysitter. Luckily, we’ve done the work and found the perfect site for you — Nanny Poppinz.
About its service
Nanny Poppinz isn’t quite as widely available as some of the other sites, but if it is in your area you’re in luck. This is a truly wonderful service for finding good child care providers. What’s more, if you need a particular babysitting service, you just tell Nanny Poppinz what your needs are. Nanny Poppinz will cover them in its services. It offers babysitters for in- and out-of-home care, 24/7 emergency services, night-time newborn support, mothers’ helpers, hotel resort babysitting, sick child care, and more.
About its staff
The company has been in business since 1992, working to make sure the professionals it hires are qualified and experienced. You just tell Nanny Poppinz what kind of babysitter you’re looking for, and its staff will do the rest of the work for you. And you can totally rely on Nanny Poppinz to find a professional babysitter. The staff will do detailed research on the babysitter, such as their backgrounds and skills. Then the staff will perform personal, face-to-face interviews in the search for your perfect babysitters.
About its charge (费用)
There are no application (申请) fees to join the service, although the company does make it difficult to find out how much you pay once you’ ve chosen a babysitter. The company provides its services for free until you find a professional for your family. Then, you’ll pay a certain amount of money depending on the type of services you need.
1. What do we know about Nanny Poppinz?A.It is popular all over the world. |
B.It provides free baby products for its users. |
C.It teaches new moms to accept their new roles. |
D.It offers various customized babysitting services. |
A.Tell users Nanny Poppinz’s long history. |
B.Show users the benefits of hiring a babysitter. |
C.Ensure that the babysitters have professional skills. |
D.Teach users how to find good babysitters themselves. |
A.When they send in an application. |
B.After the babysitters finish all tasks. |
C.After they’ve selected an able babysitter. |
D.After its staff have done the preparation work. |
Drinking water is so important for good health. When in school, you learned what water is made up of.
A.Why do you need to drink water? |
B.The rest should come from what you drink. |
C.How much water do you need to drink every day? |
D.Juices are good because they have lots of nutrients. |
E.Now let’s take a look at where your water need comes from. |
F.Water can also play an important part in protecting your body. |
G.You also learned how it is important to our body. |
【推荐2】Some pigs tend to be optimistic while others are pessimistic, according to a new research that is meaningful to animal welfare. The study, published in the journal Biology Letters, is the first to show that mood and personality interact in an animal, influencing judgment.
Asher, a researcher at the University of Newcastle's Institute of Neuroscience, and her team housed groups of pigs in two types of environment. One reflected standard commercial conditions and the other was cushier with more space and plenty of soft, deep straw. After the pigs got accustomed to these new homes over a few weeks, the researchers picked 18 pigs from each type to train and test their judgment.
“To do this, we trained each pig. In one corner of a training room there would be a bowl with chocolate sweets — pigs love them — and at the opposite side of the room there would be a bowl containing coffee beans, which pigs find bittertasting,” a researcher said.
Over a number of training trials, pigs learned to go to the bowl reliably when it was in the corner where they had figured out to expect chocolate sweets. On the contrary, they quickly learned to avoid the bowl when it was in the corner where they would expect to find the coffee beans.
The researchers next placed an unfamiliar bowl in different locations, to see how the pigs would react. Some gaily dashed to the bowl no matter what was inside, showing optimism that it would contain their favorite sweets. Others, however, behaved as though they expected it to contain coffee beans, displaying pessimism.
The findings suggest that a onesizefitsall answer to animal welfare issues does not exist. Even if pigs are just equal to bacon or other meat for some people, there is still cause for concern. Studies have suggested that how an animal is treated during its lifetime can directly affect meat quality and taste.
1. What was the study trying to figure out?A.How to make pigs happier. |
B.The similarities between humans and pigs. |
C.How living environment affected pigs' mood. |
D.How pigs' mood and personality affected their judgment. |
A.Simple. | B.More comfortable. |
C.Unpractical. | D.Less free. |
A.People should treat pigs equally. |
B.People's health relies on meat quality. |
C.People should meet pigs' various needs. |
D.People's attitude toward pigs is totally wrong. |
【推荐3】You may not know a lot of people when you start senior school.Even if you know some freshmen(新生),you still feel nervous that you don't know any upperclassmen or teachers.How are you going to make friends among this sea of unknown faces?
Most senior schools hold a freshman orientation(迎新会)before school actually starts.It is helpful not only because you learn your way around the building and get to meet fellow freshmen.That way,when you show up on your first day of school,you may already recognize a few familiar faces.
When you talk to people in t.he orientation,you'll probably find that a lot of them are feeling just like you are. They're all new to the school and don't know what to expect.Talking about a common concern with your classmates can help you develop friendships.
The work in senior school is something freshmen are probably worried about.The work in senior school builds on what you learned in junior school,giving you a more advanced knowledge of many subjects.So you may find you have more work to do or that it's a bit more challenging.If you ever find your work too difficult,teachers can give you extra help.
Senior school also has more extracurricular activities than middle school did such as clubs,music and theater groups and sports teams.This is a good time to explore your interests and try new things.
Junior school taught you the basic of academics,time management,and social skills while providing you with a little extra support and guidance.Senior school gives you the chance to learn how to be more independent and responsible.
1. According to the passage,when they come to the school on the first day freshmen usually feel .A.proud | B.nervous |
C.excited | D.afraid |
A.build up healthy bodies | B.develop friendships |
C.develop their interests | D.improve their learning ability |
A.The learning task. | B.The ability to adapt. |
C.The relationship with teachers. | D.The training in the freshman orientation. |
A.freshman at senior school | B.freshman's parents |
C.junior school students | D.upperclassmen in senior school |