Read the following paragraph and underline the topic sentence.

Before 1800, no country in the world had an average life expectancy(预期寿命) at birth beyond 40. Today there is not a country that does not. Since 1900, more years have been added to human life than in the rest of history combined, initially by reducing child death and lately by stretching life spans. Longevity is one of humanity's great achievement, yet it is seen as one of society's great headaches. The problem lies in increasing dependence of the old on the young. By 2100, the ratio of 65-plus to “working-age” people will tripe. As the world grays, growth, tax revenues and work forces will decline while spending on pensions and health care will increase.

Write a letter of thanks according to the following situation: You are doing research on environmental protection and need a book on that subject. Your friend (Chris) who is studying abroad bought the book and sent it to you. Write to him to express your gratitude, explain how important that book is, and ask about his situation. Please sign your name as Li Fei.(150-200 words)

At some times in your life, you may have taken a time management class, only to find that it is a complete waste of time because it doesn't work. Indeed, our life is wasted in all kinds of classes. Time management classes fail because there are two types of time:clock time and real time. In clock time, all time passes equally. In real time, all time is relative. Times flies or drags depending on what you're doing. Two hours can feel like 12 years. And yet our 12-year-old children seem to have grown up in only two hours. Children have no idea of time. Which time describes the world you really live in, real time or clock time? The good news is that real time is mental. You create it. Anything you create, you can manage. It's time to remove any self-limitation you have around “ not having enough time”, or today not being “ the right time” to take the action.

Read the following paragraph and choose the best topic sentence from the four options that follow. Write the corresponding let of your choice on the answer sheet.

In order to drive in the U.S., you have to go to your local Department of Motor Vehicles first, and take a written test to get your learner's permit. If you pass this test, you can practice driving so you can pass a road test and get your license. The Department of Motor Vehicles or DMV has free booklets you can go and get to study for your learner's permit. You can also access the information online and even take a practice written exam. To prepare for the road test, you can have a friend teaching you to drive or pay to take classes at a driving school. You cannot, however , practice driving by yourself. If you are caught driving with only a learner's permit, you can get into trouble with the law.

A、You cannot drive in the U.S. without passing a couple of tests.

B、Many people in the U.S. choose to practice written exams online.

C、Most Americans ask their friends to help prepare for the road test.

D、Driving with only a learner's permit in the U.S. can be dangerous.

A、 And without reflecting on the consequences of technology, they could end up bringing some of the worst of the Internet into offline life.

B、 By understanding them, we can think about how young people are growing up with technology and what impact these experiences could have. 

C、 Digital exiles are at the opposite extreme---they've been raised with minimal technology.

D、 Digital orphans have grown up with a great deal of technology access, but very little guidance.

E、The way people relate to technology---how they use the Internet---will shape with their professional opportunities, and will determine the content and experience of the Internet itself as well.

F、 A recent survey found that parents are managing their kid's use of technology in very different ways, and as a result, they are creating three distinct groups of young people: digital orphans, exiles and heirs.

G、 Digital heirs have impressive technology skills thanks largely to their parents and teachers who have encouraged and directed their technology educations, but they might face challenges in dealing with their less knowledgeable peers.

H、 Usually once they enter into the digital world, many of them will throw themselves into their online lives.

Choose the best topic sentence from the four options below. Write the corresponding letter of your choice on the answer sheet.

A、With the 30% rule, you can keep a conversation flowing in a more natural way.

B、The conversation with no new information becomes like an upside-down pyramid.

C、When you don't add new information, the conversation becomes extremely boring.

D、In some casual conversations, the same information is being repeated over and over.

Read the following paragraph and underline the topic sentence.

Before 1800, no country in the world had an average life expectancy(预期寿命) at birth beyond 40. Today there is not a country that does not. Since 1900, more years have been added to human life than in the rest of history combined, initially by reducing child death and lately by stretching life spans. Longevity is one of humanity's great achievement, yet it is seen as one of society's great headaches. The problem lies in increasing dependence of the old on the young. By 2100, the ratio of 65-plus to “working-age” people will tripe. As the world grays, growth, tax revenues and work forces will decline while spending on pensions and health care will increase.

First established in 1998, many well-known experts have been attracted to work in this research center.

My grandfather has a painting by Picasso, it must be worth a lot of money.

Many students lost marks in the exam. Because they did not read the questions carefully.

Example: After seeing an offensive mouthwash ad on television. I resolved never to buy that brand again.

After seeing an offensive mouthwash ad on television, I resolved never to buy that brand again.

11、Sales people tend to perform better in dealing with their angry customers who are emotionally skilled.