4. According to a study published last week in the journal Science, scientists have found a way to change a plant’s genes (基因) in order to make it use sunlight more quickly. Someday, the results could increase the amount of food produced around the world.

By changing a plant’s genes, the scientists were able to increase leaf growth on plants by 14-20 percent. Specifically, scientists changed the plant’s protective (保护的) system. “Normally, this system is activated when a plant gets too much sunlight,” said scientist Krishna Niyogi, co-author of the study. “When the plant senses the light, it gets rid of extra energy and creates more leaves. When the plant is in the shade, the protective system is turned off. But the process is slow.”

Stephen Long is the lead author of the study. He compared a plant’s protective system to light-adjusting glasses. “When a person wears the glasses outside during the day, the lenses (镜片) darken and lighten depending on how sunny it is. Plants do the same thing,” he said. “But in plants the adjustment can take anywhere from 10 minutes to an hour. This makes it hard for plants to get the right amount of sunlight needed to create food.”

The new study sped up the process. By changing the plant’s genes, it’s more quickly than normal to turn on and turn off the protective system. As a result, leaf growth on the plants scientists used in the study increased. Leaf growth on two plants increased by 20 percent, while leaf growth on a third plant increased by 14 percent. Scientists conducted the study on tobacco plants. But they thought the genetic modification would produce the same results in corn or rice.

5. Proper pressure can be a good thing: It can push you toward accomplishing tasks. 【小题1】. But sometimes the stress can be too much. Psychologist Travis explains that there is a best level of stress. With less than that, you may lack interest or motivation. 【小题2】 If you can reduce the stress and stay calm, you’ll have a better chance of succeeding.

Breathe out

Psychotherapist Tom suggests an effective yet simple relaxation technique: Slowly expel (排出) all the air from your lungs until there is nothing left and then count to 3 before taking the next breath normally. 【小题3】. The act of letting go of all the air lowers your shoulders and relaxes your muscles. When you are physically more relaxed, you will function better under pressure.

Keep healthy daily habits

Ensure that you are eating healthy foods. 【小题4】. Proper diet and rest may be all you need to reset your biological stress reactions to more manageable levels. In addition, regular exercise has been shown to reduce stress.

【小题5】

Regardless of how much pressure the other person is applying, or how much stress you feel, avoid reacting before you have had a chance to calmly consider what you think about the issue. Leave the room and go for a walk, make some coffee or sit alone in a quiet spot to allow yourself to decide what is the best for you.

Mike is a specialist in algebra and geometry. His only recreation is 【小题1】 (science) and technical inventions. He has published many articles in many famous journals and won several patents.

One day, he was invited to a seminar held by 【小题2】 enterprise. The participants were from all walks of life, 【小题3】 (include) officials, software programmers and futurologists.

Shortly after the seminar began, many issues were put forward, such as 【小题4】 (starve) in African countries, race discrimination in America and the conflicts in the Mid East. Permanent peace, 【小题5】 (equal) and happiness were what all the people wished for. Meanwhile, some digital 【小题6】 electronic products were presented.

Finally, Mike declared that he brought two new inventions. One was a kind of liquid 【小题7】 could remove stains on garments quickly; the other was a kind of material that could deal with poisonous chemicals in rivers. He was very outspoken. He said that pollution was very serious worldwide and that if we permitted the situation to go on, the outcome 【小题8】 (be) hard to imagine.

The organisation also encouraged people 【小题9】 (invest) money in poor countries. After the seminar, all the participants got some beautiful 【小题10】 (souvenir).

Last summer I had chance to visit Paris. That attracted me most was the Eiffel Tower, which has become a symbol of France. I was deep impressed by its height. I have never seen such a tall building ago! It is made of iron and it is about 10,000 tons in weight. There are 1,665 step from the bottom to the top. Climb the tower made me very tired, and I was very excited. I took a lot of photos in Paris.

I have much memories and experiences to share with. I am so lucky to have seen such a culture so different from my own. I will remember my trip in France forever!

2．开头和结尾已为你写好，但不计入总词数；

3．可适当增加细节，以使行文连贯。

How are you? I am chairman of Student Union, Li Hua. ___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

I am looking forward to your reply.

Yours sincerely,

Li Hua

2．可适当增加细节，以使行文连贯。