1 . First it was jogging. Then aerobics (有氧运动). Not too long ago, Americans discovered race walking.

Now Americans are into a new fitness craze. They’re taking up bicycling. Over hills and down mountainsides and across quiet country roads, Americans are busily rolling along.

The number of adults who ride for fitness is around 17 million, an increase of 70 percent over four years ago. Twice as many women as men are coming to the sport. Americans are falling in love with biking because it has speed, the benefits of jogging and beautiful scenery.

Bicycling is a very appropriate sport, which is important to people who injured their knees while jogging or whose joints are aching from aerobics. And biking is a real awakening for people who have been into race walking in the past. Race walking is as dull as watching paint dry.

The most popular kind of bicycle for people who are new to the sport is the mountain bike, which has a fixed frame with wide tires and upright handles.

Mountain bikes also have many gears (齿轮) to make it easier to climb hills. About 5 million Americans ride mountain bikes, compared with 200, 000 who rode them only five years ago.

Costs range from about $130 for a bottom-of-the-line bicycle to more than $2,700 for an expensive bicycle.

Mountain biking has attracted some people who race down the sides of mountains like a bat out of hell. But most riders ride slowly and they rarely venture far from home.

The biking craze has brought an unexpected profit (盈利) to clothing and bicycle accessory (附属品) makers. Last year, bikers paid $630 million for biking clothes and accessories.

Bicycling seems likely to continue its fantastic growth.

In the 2016 World Triathlon Series in Mexico, when Alistair came round the corner, he saw his brother about     1     (fall) onto the track. He ran towards Jonny, caught him and     2     (start) pulling him towards the finish line. The move put Jonny in second place and Alistair     3     (he) in third. It was     4     unexpected end to the race, but Alistair did not want to discuss it     5     the media. He just wanted to see his younger brother,     6     had been rushed to the medical area.

Despite     7     (argument) over “stupid things” now and then, Alistair agrees that     8     (have) a brother is an advantage.

    9     (watch) by millions, the ending to the race has divided opinions: should the brothers have been disqualified or     10     (high) praised for their actions? But for Alistair, this decision was easy to explain: At that moment, he was no longer an athlete aiming for a medal—he was just a brother.

5 . Competition in the Olympics should be between athletes who use their own strength or speed. If some athletes don’t follow the rules, it ruins the fun for everyone connected with the game. It also gives an extremely unfair advantage to athletes using drugs. So I think athletes should be tested for drugs.

—Jim from Atlanta

Drug use among top athletes has long been a problem. Without drug tests, the Olympics would be about who uses the most drugs, not who trains the hardest and has the most athletic skills. Also drugs do harm to people’s health and sometimes even kill people.

—David from Houston

Why should athletes be allowed to compete when it’s not really they who are actually competing? It’s the drugs that do all the work. Athletes who use drugs are like runners with roller skates. It’s cheating and irresponsible, which must be strictly forbidden. It’s unfair to other competitors who don’t use drugs.

—Bruce from Chicago

Most sports athletes are held to a standard of being drug-free. Olympians should not be held any differently. They take part in highly competitive sports and win medals for their country. Testing the athletes for drugs must be done in every country and every sport. No drug test would be unfair to athletes who don’t use drugs.

—Sam from Los Angeles

Although popular opinion is against athletes’ using drugs, I believe drugs do help make the Olympic sports more wonderful. I enjoy seeing human beings achieving things that couldn’t be done with normal conditioning. I enjoy seeing stronger, faster and longer performances by making good use of drugs. I don’t see the necessity of drug tests.

—Jack from New York

6 . For the first time in its history, the International Olympic Committee has allowed a team of refugees to compete at the Games. All of the team’s members were forced to leave their home countries. Now they’ve come together to compete under the Olympic flag instead.

Making it to the Olympics is something eighteen-year-old swimmer Yusra has always dreamed of. But just last year, she was swimming for her life. She and her sister were forced to leave their home in Syria because of the war there. They were trying to get to Greece in a rubber dinghy (橡皮艇) with eighteen other refugees, when their boat broke down and began filling with water. Most of the people on board couldn’t swim, so she and her sister jumped in to help push it to shore.

Three hours later, they made it to safety, and eventually to Germany as refugees. Refugees are people who have left their home country because their lives are threatened by war, bad treatment or violence---often because of their race, gender or beliefs. Around the world, more than 60 million people are in this situation. And some of them, like Yusra, are elite athletes who have trained all their lives to compete at the highest level, only to have that chance taken away.

Now, a team of ten, including swimmers, runners, and judokas from Syria, South Sudan, Ethiopia and Congo have been given the chance to compete at the Games under the Olympic flag. They’ve also been given their own coaches, officials, uniforms and a chef, all paid for by the IOC. And in the past few months they’ve been training hard. The IOC says it wants the team to inspire and give hope to other refugees, and draw attention to the issues millions of other around the world are facing. And these guys say they are up to the task whether they win gold or not.

“These refugee athletes will show the world that despite the unimaginable tragedies that they have faced, anyone can contribute to society through their talent, skills and strength of the human spirit,” the statement continues.

On a quiet morning, about 70 people were practicing the ancient art of tai chi, outside of the library in Salt Lake City, Utah. They are not    1     well-trained   group of exercisers,   but rather a class of participants who are    2    (most) homeless. The class focuses    3     (little) on mastering the exercise and more on    4    (build) a community. People have said the class relieves their stress, encourages them to get into a routine and make new friends.

Bernie   and Marita Hart, a    5    (retire) couple, began to run the free program   three years ago. They started it by approaching   homeless people    6     were pushing grocery carts near the Salt Lake City Public Library and inviting them to try    7     Hart said her   favorite part of the program has been watching the friendships among participants. They love seeing the positive impact the class    8    (have) on people's lives.

When the Harts are out of town, tai chi does not stop. Attendees take turns teaching the classes.

"Homeless people    9    (tell) what to do every place they go, but we want to encourage them   to   be    10    (leader)," Bernie   Hart   said. "They   don't   need   sympathy,   they   need something that works."

8 . If you're out for a run, what difference does it make if you're able to tough it out for another 50 seconds? If you're less than a minute from the top of the hill, that extra time can make the difference between having reached your goal and snatching defeat from the jaws of victory.

How do you get those extra seconds of energy? A research team at the Texes Tech University developed a study to measure what effect listening to music would have on exercise tolerance. The researchers based the study on a stress testing. As part of the testing, they noted any changes in heart rate and blood pressure as participants underwent physically stressful exercise.

The tests were done on treadmills (跑步机), which increased in both speed and incline (坡度) through three stages. In the final stage, the treadmills moved at 10 miles per hour at a 14-percent grade. Most of these tests were designed to last up to 40 minutes. The average gym-goers lasted 30 minutes. For this study, they divided 127 participants into two groups. One listened to upbeat(快节奏) music, while the other group had earbuds in but did not listen to music.

The group that listened to music was able to outlast the non-music group by an average of 50.6 seconds. Again, being able to go an extra minute may seem like a no-brainer ,but “after 30 minutes, you feel like you are running up a mountain, so even being able to go 50 seconds longer means a lot," said the study's lead author, Waseem Shami, MD.

The study has confirmed something runners and gym-goers have suspected for years: Listening to music during workout can be beneficial to your endurance. "Our findings reinforce the idea that upbeat music can help you exercise longer and stick with a daily exercise routine," said Shami. When doctors are recommending exercise, they might suggest listening to music, too."

9 . Why play games? Because they are fun, and a lot more besides, following the rules, planning your next move, acting as a team member…. These are all “game” ideas that you will come across throughout your life.

Think about some of the games you played as a young child, such as rope-jumping and hide-and-seek. Such games are entertaining and fun. But perhaps more importantly, they translate life into exciting dramas that teach children some of the basic rules they will be expected to follow the rest of their lives, such as taking turns and cooperating.

Many children’s games have a practical side. Children around the world play games that prepare them for work they will do as grown-ups. For instance, some Saudi Arabian children play a game called bones，which sharpens the hand-eye coordination(协调)needed in hunting.

Many sports encourage national or local pride. The most famous games of all, the Olympic Games, bring athletes from around the world together to take part in friendly competition. People who watch the event wave flags, knowing that a gold medal is a win for an entire country, not just the athlete who earned it. For countries experiencing natural disasters or war, an Olympic win can mean so much.

Sports are also an event that unites people. Soccer is the most popular sport in the world. People on all continents play it—some for fun and some for a living. Nicolette Iribarne, a Californian soccer player, has discovered a way to spread hope through soccer. He created a foundation to provide poor children with not only soccer balls but also a promising future.

Next time you play your favorite game or sport, think about why you enjoy it, what skills are needed, and whether these skills will help you in other aspects of your life.

10 . On Sunday 23 April, most than 30,000 people participated in the 2017 London Marathon, running 26.2 miles (42.2 kilometres)around the city center.

The London Marathon has taken place every year since 1981. At the first one, just 6, 225 people completed the course, and since then it has grown into one of the biggest sporting events in the world. It is one of the ‘World Marathon Majors’, which is a competition made up of six global marathon events. The overall male and female winners receive $1 million in prize money between them There are eleven people who have run every London Marathon since it began—they call themselves the ‘Ever Presents.’

This year, the winners of the London Marathon were surprisingly both from Kenya—Daniel Wanjiru, who finished in 2 hours and 5 minutes, and Mary Keitany, whose time was 2 hours and 17 minutes.

However, most marathon runners are not professional athletes. They are amateurs who have trained for months to raise money for charity or just as a personal challenge. For example, Tom Harrison took three days just to reach the run’s halfway point, as he is crawling the course on his hands and knees dressed as a gorilla(大猩猩), trying to raise money and attention for the charity ‘The Gorilla Organisation’.

Matthew Rees was another runner to encourage people, as he stopped just before the finish line to help David Wyeth   run the last 200m.They did not know each other before, but Matthew saw that David was exhausted and possibly close to collapsing, and wanted to help him finish.

Every year there are lots of touching stories like this from the London Marathon, and it is a huge achievement even to run the 26.2 miles !