It was announced that China had achieved success in drilling combustible ice(可燃冰)，a frozen     1     (mix)of water and natural gas, from the South China Sea.     2     (official)known as methane hydrates(甲烷水合物), combustible ice produces a high amount of energy when burnt and its chemical reaction produces nothing but dioxide and water.

Combustible ice, both clean and energy-intensive,     3     (consider)the fuel of the future. Many countries, including the United States and Japan,     4     (conduct) research on combustible ice, but extracting(提取)it from the bottom of the sea has been a common problem     5     (trouble)all of them. But the Chinese team succeeded in drilling combustible ice for nearly eight days,     6     was a big breakthrough.

However, it is too early     7     (say)a new energy source has been found. The world's total combustible ice reserves range from 280 trillion cubic meters to 2,800 trillion cubic meters, which, if extracted, could meet the world's gas demands     8     80 to 800 years at current rates. But the successful test drilling of combustible ice does not mean it can be extracted for     9     (industry)use. China has to solve many problems before it can use combustible ice as a source of energy. It’s thought that only by 2025 at     10     earliest might people be able to see realistic commercial values.

According to a report released by the United Nations, there were 815 million undernourished（营养不良的）people in the world in 2016. Yet, 1.3 billion tons of food     1    （waste）every year around the world， which is about one-third of all food produced each year, according to the UN's Food and Agriculture Organization.

    2    （get）a better understanding of different countries’ food waste problems, the Economist Intelligence Unit recently surveyed 34 nations according to their food system sustainability（可持续性）. According to the report，France topped the list of food sustainability，followed by Japan and Germany.

The    3    （perform）of these countries is largely related to their policies to deal with food waste. For example，France was the first country to pass laws to ban（禁止）food waste. In France, it's illegal for supermarkets to throw away    4    （sell）food, and French restaurants must provide doggy bags for people's leftovers.

Germany is trying to deal with the problem by reforming expiration dates（到期日）. “We found in our study that many people believed they should throw away products    5    the `best before' date has expired,” Martin Kranert, chair of Stuttgart University's waste management department, told Deutsche Welle. “This is not at all case, and such a lack of knowledge is the first thing     6    has to change.”

Some countries are still falling behind when it comes to     7    （prevent）food waste, however. For example, the United Arab Emirates wastes the most food, with each of its citizens throwing away about 1,000 kilograms every year     8    average.

China has been working hard to reduce food waste. In early 2013, the country's Clean Your Plate Campaign started,     9    （encourage）people not to waste anything on their plate.

“If people are more aware of the amount of food waste they produce and everyone plays a role in reducing their personal food waste, we can do     10    （well）as a community,” Joyce Chan from the Foodlink Foundation, a Hong Kong charity dedicated to reducing food waste, told China Daily.

I am writing in reply to your article about homelessness in Ledchester as it raises questions about whether or how we should give money to charity.

I think     1     more effective way to give money is to buy things in one of the many charity shops in Ledchester such as the Oxfam shop. This isn’t really charity as you are buying something,     2    you know the money is going to a good cause.

In recent years, as is known to all of us, there     3     (be) a lot of big events organized to raise money for charity. Many will remember “Live Aid” in 1985. Lots of famous bands     4     (get) together to hold a concert and make a record with all the money     5     (go) to Ethiopia because of the food     6    (short) there. The BBC also has a “Children in Need” day     7     (year). In one sense you could say that these events are very successful as they raise a lot of money. However, I don’t believe that these events solve the real problems,     8     , in my view, just allow people to feel good about themselves for a day and then forget about charity and problems in the     9    (develop) world for the rest of the year. My wife and I decided to support a child. We give a certain amount of money every month and this goes to pay for the education of a girl in Ethiopia. I would encourage your readers to support a child too. We don’t know if it is the best way to help, but    10    least it is something.

Yours faithfully,

Tom Blinson

South Korean     1     (society) satire "Parasite" won the Oscar for best picture on Sunday, becoming the first ever non-English-language film     2     (seize) the top honor.

"Parasite," about the gap between rich     3     poor in modern Seoul, won     4     total of four Oscars, including best director and screеnplay for Bong Joon Ho and best international feature.

Korean director Bong Joon Ho's black comedy-thriller, about an impoverished family     5     scheme their way into an upper-crust household,     6     (artful) explores resentment between the haves and the have-nots.

Even more striking is     7     (it) deep humanity: both the scammers and the scammed earn our sympathy. Parasite is today's answer to filmmaker Jean Renoir's famous line, "The awful thing about life is this: everyone has their     8     (reason)."

"I never thought I would win," Bong said while     9     (accept) his best director Oscar. Paying tribute to his four fellow director nominees he said, "I would like to get a Texas chainsaw and split the Oscar     10     five and share it all with you."

Bigger isn't always better. People who are doubtful about this argument just need to look at smartphones and personal computers, which have served     1     the technological driving force behind the social development of the past century. It is the continual shrinkage(缩小)of components that has caused the explosion of computing power and     2     (enable) these gadgets(小工具) to be accessible to people across the world.

    3     (inspire) by this, researchers and scientists have been working on areas     4     making things small may mean big results. And this year, the Nobel Prize has broken the tradition of celebrating big by presenting the biggest prizes to discoveries on the     5     (small) scales.

The Nobel Prize in Physiology or Medicine     6     (award) (细胞水平)experiment. The committee gave the award to Yoshinori Ohsumi of the Tokyo Institute of Technology, for his research on "autophagy",     7     "self-eating" process seen in cells.

What's more, in recognition of their working on the strange properties of matter in extreme states and     8     (take) their research all the way down to ap atomic scale, the Nobel Prize for physics went to three British -born scientists who     9     (current) work in the U.S.

Another exceptional new field is that of nano-technology. The Nobel Prize in Chemistry went to a scientist    10     managed to build the world's tiniest machines out of molecules. Small though the subjects are, the benefits of the scientists’ research are set to be huge. More importantly, their invention may even eventually be turned into products that benefit mankind.

A new study has found that the number of American teenagers using Facebook    1    （be）dropping. Many turn instead    2    YouTube, Instagram and Snapchat.

The study    3    （make）by the U. S-based Pew Research Center found that 51 percent of American teens between the ages of 13 to 17 said they use Facebook the most. This was a large drop from 2015,    4    71 percent of teens in that age group reported using the social media service.

The study found that YouTube is now the most popular internet service for teens, with 85 percent    5    （say）they use it very often. The second is Instagram, at 72 percent. 69 percent of teens said they    6    （current）use Snapchat, while 32 percent use Twitter. Less than 10 percent reported using Tumblr or Reddit.

In March, another Pew study found that 68 percent of adults said they were Facebook    7    （use）. Of those, 74 percent said they used the social media service daily. About half of the adults reported using Facebook several times a day

Results of the latest study    8    （base）on interviews with 743 teens and more than 1,000 parents during March and April 2020.

The study also found that 95 percent of teens reported they either owned a smartphone    9    had a way of using one. This marked    10    18 percent increase over a similar study from 2015.

A great fire has destroyed the old cathedral (大教堂) of Notre Dame (巴黎圣母院) in Paris, one of France’ s     1    (famous) landmarks.

Thousands of people gathered in the streets around the cathedral, watching the flames in silence. Some of them could be seen crying. Watching such a famous old building     2    (destroy) is extremely     3     (shock) to any French person.

No other site represents France like Notre Dame Cathedral,     4     receives almost 13 million visitors each year, more than the Eiffel Tower. The Eiffel Tower, is little more than a century old while Notre Dame Cathedral     5     (stand) tall above Paris since the 1200s. It has given     6     (it) name to one of the country’s literary masterpieces. Victor Hugo’s The Hunchback of Notre Dame (《钟楼怪人》) is known     7    the French simply as Notre Dame de Paris.

The three large rose windows have been destroyed     8     the fire. Fortunately, the main structure,     9    (include) the two bell towers, has been saved. Also the most     10    (value) cultural relics have survived.