Do you know about Dolly, a famous sheep? She was created by cloning more than fifteen years ago in Scotland. Cloning is famous throughout 【小题1】 world. It is a process 【小题2】(use) to make an animal that is exactly like its parent. So far, scientists 【小题3】 (clone) rabbits, sheep, cows, mice, pigs and some other animals.

But what makes cloning possible? It’s DNA. There is DNA in most living things, 【小题4】 (include) human beings. Your DNA is the same in every part of your body. For example, your fingernails have the same DNA as your hair. You have your own DNA, 【小题5】 is similar to your parents’, but not the same. However, Dolly’s DNA is the same as 【小题6】 of the sheep she was cloned from.

There's no doubt that cloning can help save those animals in danger. It can also be 【小题7】 (benefit) to human beings. 【小题8】 its help, scientists are able to explore more ways to treat many serious diseases. However, cloning could be used in some ways to harm 【小题9】 (social), too. So I wish all governments 【小题10】(can) make laws to make sure it can be used properly.

The earth is becoming warmer. How has this come about? There is no doubt that 【小题1】 is human activity that has caused this global warming rather than a 【小题2】 (nature) phenomenon.

All scientists subscribe to the view that the temperature rise is due to the 【小题3】 (burn) of fossil fuels to produce energy. Some byproducts of this process are called “greenhouse” gases, the most important one of 【小题4】 is carbon dioxide. Without the “greenhouse” effect, the earth 【小题5】 (be) too much cooler than it is. So we need those gases. 【小题6】 when we add huge quantities of extra carbon dioxide into the air, the problem occurs. More heat energy 【小题7】 (trap) in the air causes the global temperature to go up.

However, the attitudes of scientists towards the temperature rise are 【小题8】 (complete) different. Some think the ongoing rise will lead to disasters while others are opposed 【小题9】 the view. They even think more carbon dioxide is actually a positive thing.

Who are right? Only when the fact comes out, 【小题10】 we know it.

Winter sports were already popular in China a thousand years ago in the form of Bingxi (冰嬉), or play on ice. Bingxi as 【小题1】form of performance for the court began in the Song Dynasty and reached its peak during Qing. A Bingxi painting in the collection of the Palace Museum portrays scenes of Bingxi during the Qing Dynasty. A closer look at the painting will show that there are many 【小题2】 (similarity) between how ancient Chinese people enjoyed games on ice and modern day 【小题3】 (compete) events at the Winter Olympic Games.

In the painting, the emperor, 【小题4】 (seat) inside his ice bed, was watching skaters compete 【小题5】(fierce). Three types of ice skating were performed, the first one of 【小题6】 is speed race, similar to modern speed skating. Participants raced to the emperor’s ice bed from 2 to 3 kilometers away. 【小题7】 reached the emperor first won first prize. The second is figure skating. Jumps, spins and pair work moves common in modern day figure skating can all be found in the painting. The third is the soccer on ice. Participants in two teams skated, kicked and tried to score goals. If the “tool” for scoring goals 【小题8】 (change) from legs to sticks, it is highly comparable to hockey.

To this day, the interest 【小题9】 winter sports in Chinese people has never decreased. Each winter, in Beihai and Shichahai of Beijing, people are still enjoying 【小题10】 (they) forms of Bingxi.