5 . A new study out of Canada suggests teenagers should spend less time looking at screens and more time getting involved in activities. The findings published in the journal Preventive Medicine were based on a survey of 28,000 7th graders in British Columbia.

They answered questions about how much time they spent watching TV, streaming videos ₉ playing video games and how much time they spent on after-school activities like sports and music programs. Then they ranked how good they felt about each day when they woke up. From their answers, researchers concluded that teens who spent more time on activities were mentally healthier and less anxious and depressed than those who spent more time on screens. And the study suggested that extra screen time was especially harmful to girls. For them, researchers say the negative effects were stronger.

So how much screen time is too much? The Canadian Pediatric Society says all teens should have less than two hours of screen time per day and that guideline was factored into the study. But it’s important to point out that the information about it was gathered between 2014 and 2018, years before the CO VID hit. And this year, with fewer opportunities to see friends and participate in after-school events, teenagers have shown higher levels of depression and anxiety according to other research.

The lead author of the Canadian study says even though it’s harder to do, it’s still important to find ways for teens to safely get involved with programs and hobbies away from screens.

7 . As a short-distance track and field runner at high school and college, I often found myself wondering which of the eight or sometimes nine lanes (跑道) on the track was the fastest. It was conventional wisdom that the middle lanes — lanes three through six — were the best.

This idea, in a way, is baked into the rules of track and field. In events with multiple heats — from the college level all the way to the Olympics — the people who run faster times in earlier heats are assigned to middle lanes in later heats. In other words, the fastest runners are rewarded with what are, supposedly, better lane assignment (分配).

Using 20 years of track and field data from the International Association of Athletics Federations, I found that the long-held beliefs about lane advantages are not supported by the data. And in fact, for the 200-meter sprint (冲刺), the evidence suggests that lanes often regarded as the least desirable are actually the fastest.

In most races, the fastest runners are assigned to the middle lanes according to the competition rules. Not surprisingly, the fastest runners — who are in the middle lanes — often win. Are these racers winning because those lanes are the fastest or because those runners tend to be the fastest?

Next time you're watching any of the shorter track and field events in the Olympics, listen and see if anyone repeats the old adage that the middle lanes are the fastest. The data shows this isn't true, so if someone in the outside lanes takes a surprise gold, you'll know it is not because of their lane assignment, but because they were a slow qualifier (入围者).

August 16, 2016 runners Abbey D' Agostino (USA) and Nikki Hamblin (New Zealand) touched the world while they _________ in the women's 5,000-metre event in Rio. During the race, somewhere around 3,200 metres, Abbey and Nikki _________ each other. Nikki was running when she suddenly had to _________   to avoid contact with another runner. Then Abbey bumped into her from the back, bringing them _________to the ground. As Abbey was getting up, she noticed Nikki was hurt and needed help. While their competitors carried on with the race, Abbey _________   to help up Nikki, who had taken a hard fall and was lying on the track.

In an interview later, Nikki recalled how the suddenness of the crash and fall influenced her. "When I went down it was like, 'What's happening? Why am I on the ground?' And suddenly there's this hand on my shoulder, like '   _________.We have to finish this! ' I'm so _________and touched that she did that." Nikki said.

_________, Abbey had hurt her knee in the fall and had difficulty walking. Instead of _________ in the race, Nikki helped to __________ her injured opponent (对手) along the way. Abbey then tried to __________ Nikki to go on without her. However, Nikki provided her with __________ to walk slowly towards the finish line. Both girls finally made it to the finish line.

__________ Nikki came in second to last and Abbey came in last with her twisted ankle, they still got moved to the finals. What a __________ race!

"I'm so thankful for Abbey for doing that for me. That girl is the Olympic spirit right there." Nikki said. The simple act has become a   __________of the Olympic spirit. Their good sportsmanship got them into the finals.