题目内容
（请给出正确答案）
Why we use index in database？ How many indexes is the maximum in one
table as your suggestion？
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We could start with the advantages of mobile phones. There are many things that we could do with mobile phones. With the advancement of technology，more and more features are being added to the mobile phones which make them more useful. In addition to making calls，mobile phones also support a wide variety of other services such as text messaging，email，Internet access，business applications，gaming and photography. We can bring them everywhere，and can be reached by others anytime. They make the world smaller，bringing people together no matter where they are.
But we could have some risks when using our mobile phones. We may have accidents when we use them while driving. Some studies show that mobile phones can do harm to our bodies;and materials in mobile phones could damage our environment.
Since there are so many risks，why do we still have mobile phones？This is because these risks or disadvantages can be overcome. For example，while we are driving we can easily pull up our car if we really need to use the phone. Mobile phone manufacturers are reducing the radiation of mobile phones to avoid health risks.
Though there are both pros and cons of using mobile phones，we could easily see that there are more advantages than disadvantages. Moreover，mobile phones are becoming cheaper，which might be another reason why mobile phones are increasingly used today.
1. Which of the following functions is NOT mentioned in the passage？
A. Text messaging.
B. Camera.
C. GPS.
2. What risks might mobile phones cause？
A. Traffic accidents and health problems.
B. Environmental damage.
C. Both A and B.
3. What are mobile phone manufacturers doing to prevent mobile phone users from health risks？
A. They are reducing the radiation of mobile phones.
B. They are trying to persuade people to use mobile phones less.
C. They are developing new models of mobile phones.
4. Why do people still use mobile phones despite their disadvantages？
A. Because people don’t believe that mobile phones have any disadvantages.
B. Because the disadvantages of mobile phones can be avoided.
C. Because people cannot live without mobile phones.
5. According to the last paragraph，why are mobile phones increasingly being used today？
A. They are safer.
B. They have more functions.
C. They are becoming cheaper.
概括段落大意和补全句子。
Our Muscles
(1)When we think of muscles, we might often picture a bodybuilder with big arm and leg muscles. But our muscles do not have to look like that to work well.
(2)As a matter of fact, every time we write our name, we use the 20 different muscles in our hand. Every time our heart beats, we use our cardiac muscle(心肌) . When we eat our food, we use our tongue muscles. We even use muscles when we open and close our eyes. In fact, every time we move, we use some of the muscles in our body.
(3)A muscle is made of tiny fibers. Fiber is a type of tissue that feels a little like a rubber band. Thousands of these fibers are packed together to make a single muscle. We all have the same number of muscles----about 700 or so. Men and women with big muscles simply have thicker bundles of fibers.
(4)There are three different types of muscles in our body. Smooth muscles are the ones that we cannot control. They work quietly to keep our body running. Also, they are the ones that help us to absorb our food. The cardiac muscle makes the heart pump blood in and out. Skeletal muscles are the ones that we can control. These are the muscles that we use to raise our hands, or ride our bicycles.
(5)Even our face often uses muscles. But if we want to save our energy, try smiling instead of frowning. Remember that it takes 17 muscles in our face to smile, but 43 muscles to frown!
Task 1
1. Paragraph (1)
2. Paragraph (2)
3. Paragraph (3)
4. Paragraph (4)
5. Paragraph (5)
A. What a muscle consists of
B. When we use our muscles
C. How people think of muscles
D. What kind of muscles we have
E. Why we have different muscles
F. Why we should smile rather than frown
Task 2
6. Muscles don’t have to be very big____________.
7. Our muscles are working _______________.
8. A single muscle contains __________________.
9. Smooth muscle help us _________________.
10. Smiling uses less energy than ___________________.
A. frowning
B. a lot of fibers
C. to digest food
D. to function properly
E. whenever we are happy
F. whenever we do something
Read the following paragraph and select the irrelevant sentence.
Physical gestures and body language have different meanings in different cultures, and misunderstanding these signals can sometimes be embarrassing.So we must learn how to tolerate.Although I had spent a lot of time among non-Americans, I had never realized what this could mean in practical terms.I had an experience that taught me well, however.Some years ago, I organized and accompanied a small group of visiting foreign students to New York for four days of sightseeing by bus.Because these students were rather young, and because New York was such an overwhelming city, I was constantly counting heads to be sure we hadn't lost anyone.In the USA , it is very common to count people or things by pointing the index finger and, of course, I used this method.One young man became extremely quiet and pensive, and I thought that perhaps he wasn't enjoying himself.When I asked him what the matter was, he replied, In my country, we count people with our eyes.We use our fingers to count pigs.
A.Physical gestures and body language have different meanings in different cultures, and misunderstanding these signals can sometimes be embarrassing
B.So we must learn how to tolerate
C.Although I had spent a lot of time among non-Americans, I had never realized what this could mean in practical terms
D.I had an experience that taught me well, however
West lake College in Virginia will start a laptop computer program that allows students to do school work anywhere they want. Within five years,each of the 1,500 students at the college will receive a laptop. The laptops are a part of a $10 million computer program at West lake, a 110-year-old college. The students with laptops will also have access to the Internet. In addition, they will be able to use e-mail to “speak”with their teachers, their classmates, and their families. However, the most important part of the laptop program is that students will be able to use computers without going to computer labs. They can work with it at home, in a fast-food restaurant or under the trees-anywhere at all!
Because of the many changes in computer technology, laptop use in higher education, such as colleges and universities, is workable. As laptops become more powerful, they become more similar to desktop computers. In addition, the portable computers can connect students to not only Internet, but also libraries and other resources. State higher-education officials are studying how laptops can help students.
State Officials also are testing laptop programs at other universities,too.
At West lake College, more than 60 percent of the staff use the computers. The laptops will allow all teachers to use computers in their lessons. As one West lake teacher said, “Here we are in the middle of Virginia and we’re giving students a window on the world. They can see everything and do everything.”
1.The main purpose of the laptop program is to give each student a laptop to ____.
A、access the Internet
B、work at home
C、use for their schoolwork
D、connect them to libraries
2. Why is the word “speak” in the second paragraph in quotation mark？____
A、They don’t really talk
B、They use the computer language
C、Laptops have speakers
D、None of the above reasons is correct
3. Which of the following is true about West lake College？____
A、It is an old college in America
B、All teachers use computers
C、1,500 students have laptops
D、Students there can do everything
4.A window on the world in the last paragraph means that students can____.
A、attend lectures on information technology
B、travel around the world
C、get information from around the world
D、have free laptops
5.What can we infer(推断) from this passage？____
A、The program is successful
B、The program is not workable
C、The program is too expensive
D、We don’t know the result yet
A.strongly
B.probably
C.wisely
D.properly
