1 . Cheating in sport is as old as sport itself. The athletes of ancient Greece used potions to strengthen themselves before a contest, and their modern counterparts have everything from anabolic steroids (类固醇) to growth hormones with which to_________their bodies. These days, however, such stimulants are_________, and those athletes must therefore face the challenges of anti-doping (反兴奋剂) agencies.

The agencies have had remarkable success. Testing for anabolic steroids was introduced in the 1970s, and the incidence of cheating seems to have_________dramatically as a result. The tests, however, are not entirely_________. And a study just published in the Journal of Clinical Endocrinology & Metabolism by Jenny Jakobsson Schulze and her colleagues at the Karolinska Institute in Sweden suggests that an individual’s genetic make-up could_________the tests in two different ways. One genotype, may allow athletes who use anabolic steroids to escape detection altogether. Another may actually be convicting (给……定罪) the innocent.

The test employed for testosterone (睾酮素) abuse usually relies on measuring the_________of two chemicals found in the urine (尿液): TG. and EG.. Any ratio above four of the former to the latter is considered_________and leads to more tests. However, the production of TG is controlled by a gene called UGT2B17. This gene comes in two varieties, one of which has a part missing and therefore does not work properly. A person may thus have none, one or two working copies of UGT2B17, since he inherits one copy from each parent. Dr. Schulze_________that different numbers of working copies would produce different test results. She therefore gave healthy male volunteers whose genes had been examined a single 360mg shot of testosterone — the standard dose for legal medical use — and checked their urine to see whether the shot could be_________.

The result was remarkable. Nearly half of the men who carried no functional copies of UGT2B17 would have gone undetected in the standard doping test.____________, 14% of those with two functional copies of the gene were over the detection threshold (门槛) before they had even received an injection. The researchers estimate this would give a ____________rate of 9% in a random population of young men.

Dr. Schulze also says there is substantial____________variation in UGT2B17 genotypes. Two-thirds of Asians have no functional copies of the gene which means they have a naturally____________ratio of TG to EG, compared with under a tenth of Caucasians (白种人) — something the anti-doping bodies may wish to take into account.

In the meantime, Dr. Schulz’s study does seem to offer innocents a way of____________themselves. Athletes who will travel to Paris for the Olympic games may be wise to travel armed not only with courage and the “spirit of Olympianism”, but also with a copy of their____________, just in case.

With the International Conference on Food Loss and Waste closed on Saturday in Jinan, Shandong Province, the country has sent a signal to     1     world that China will deal with issues concerning food security by reducing loss and waste in agriculture. With the theme of reducing food loss and food waste and promoting     2     (globe) food security, the three-day event     3     (hold) both online and offline attracted more than 300 participants.

The current world grain production is about 2.8 billion tons a year. Therefore, the loss of only one percentage     4     (be) equal to the loss of 28 million tons of food. This can feed about 70 million people.

In recent years, China     5     (make) great progress in controlling loss and waste in food, with main efforts including upgrading facilities and     6     (equip). In Shandong Province, China’s major grain producer, the Sinograin (中粮集团) grain storage site is equipped with 4,500 high-definition cameras and 280,000 temperature sensors     7     (ensure) that the stock (储备) is in the best condition. Data shows that during China’s 13th Five-Year Plan period (2016-2020) , about 13 million tons of food had been saved     8     (year) after production.

We cannot end hunger     9     we do not deal with the high levels of food loss and waste. Cooperation and innovations (创新) in business models, technologies and digital solutions could all contribute     10     reducing food loss and waste.

6 . Under the background of the slow growth of its total population to 1.44 billion, China has seen a sharp rise in older adults over the past decade, solidifying the country’s rapidly aging pattern, the latest national census (人口普查) data shows. The population on the Chinese mainland increased by an average of 0.53 percent annually during the past 10 years to 1.41 billion, compared with an annual growth rate of 0.57 percent from 2000 to 2010, according to the 7th national census published by the National Bureau of Statistics.

“The growth of the total population has slowed down but remains at a steady pace,” Ning Jizhe, head of the bureau, said at a news conference. “Based on trends in recent years, China’s population will grow at an increasingly slow rate in the future while remaining above 1.4 billion.” The increasing elderly population has become a defining feature of the past decade.

Ning said an aging society will set the tone for China's population structure for a long time, presenting challenges and opportunities. “A graying population will pile pressure on supply of labor force and social services, as well as adding to families’ elderly care burden. But more elderly people could also motivate consumption of products and services targeting this age group, and advance the development of some technologies,” he said.

Ning added that those between the ages of 60 and 69, who are equipped with knowledge, experience and skills and are generally in good health, make up nearly 56 percent of all older adults. “Their potential to continue making contributions to society and playing a constructive role is big,” he responded to a question on the outlook for raising the retirement age and carrying out other potential measures aimed at addressing the aging trend. Some population economists also said the latest number and proportion (比例) of elderly are largely within predictions, and the aging trend will continue for a long time.

8 . Working from home has been a long-held dream for many employees craving more flexible work arrangements and comfort. With the fantasy coming true because of the outbreak of COVID-19, however, quite a few people find it less romantic than expected. Amid the ongoing epidemic, a large number of Chinese companies have ordered employees to work from home, looking to control the spread of the virus as staff members return from the Spring Festival travel rush.

Allowing employees to work from home-even if they are not symptomatic-and enabling virtual meetings could help limit the spread of the virus and assuage employees’ fears about exposure.

But there’s another side to the coin. As millions of people started to work at home, people found video communication difficult. Many telecommuting platforms, including DingTalk, an all-in-one mobile workplace from Alibaba, went through temporary outages due to surging demand.

Fu Yangang, a product manager at a house trading company in Beijing, found he couldn’t receive any messages from colleagues during an online meeting at home on Tuesday, and neither could they. Similar problems arose when they switched to Zoom, a California-based video communication app which provides remote conferencing services.

Residences filled with distractions such as spouses, parents, kids or pets set up another obstacle for many employees working from home. Xia Baigi, who works for an Internet company in Beijing, was required to stay at home in Jilin Province until Feb.10, but has found what was an oft-wished for working style a hindrance to productivity. Her parents, who don’t have much to do, suddenly became concerned about her job and asked many questions. “I love my mom and dad, but their current behavior just adds stress and strain,” she said. “Sometimes I have to lock myself in my own room to avoid their enthusiasm.”

For people who are able to stay as productive as they would in an office environment, they came across a different problem： “surprisingly” longer working time at home. Working for an investment company in Shanghai, Zhang Fei felt he could never escape from his job working at home in Shandong Province, which makes time management a whole lot messier. “There is no longer a’ work’ and’ no work’ time. My work comes calling at all hours, which can keep me at a frenetic pace,” he said. With the return date drawing closer, he said, he never felt so excited about being back at the office.

A simple badge (徽章) is playing an important role in helping lost seniors return home. By scanning a QR code on a plastic badge, anyone with a smartphone can reach the person’s emergency contact     1     (immediate). “It’s efficient and     2     (save) effort,” said Li Caoliang, head of the Lei Feng police station in Fushun, Liaoning province.

The idea came to Li and his     3     (colleague) four years ago when dealing with more than 200 lost seniors in a year. Some of the old people got lost because they had illnesses such as memory     4     (lose) or Alzheimer’s. They couldn’t tell their identity, address or phone number. Sometimes, the officers had to spend hours     5     (try) to figure out who to call from vague descriptions by the lost seniors. In some cases, the lost seniors had to stay overnight at the station before their families     6     (contact). The number of lost seniors has dropped to around 30 a year since     7     the police developed came into use.

China has 264 million old people, accounting     8     18.7 percent of its population according to its seventh population census     9     (conduct) last year. Wang Jiajuan,     10     has long focused on improving public services for an aging society, says the innovative QR code ID helps guarantee the travel safety of seniors.