In 1983,thousands of runners from all over the world gathered in Australia to take part in the West field Sydney-Melbourne Ultramarathon—a distance of 875 kilometers. The first man to win this race was 61-year-old potato farmer Cliff Young.

When Cliff showed up in the race, he stuck out like a sore thumb. While all the other participants wore professional running equipment, Cliff was dressed as if he had just retumed from the field. Wearing his everyday clothes and work boots, he quickly attracted the attention of reportlers present,

"I grew up on a farm where we couldn't afford horses or tractors(拖拉机).Whenever the storms would roll in, I'd have to go out and round up the sheep," Clif told reporters."Sometimes I'd have to run those 2,000 sheep on 2,000 acres for two or three days.It took a long time, but I'd always catch them. I believe I can run this race. "No one actually believed him. Most competitors were in their 20s and early 30s,with years of training and marathon experience.

On the first day, Cliff was left far behind. But he had one advantage that no one had expected. All the other runners had been training to run for 18 hours a day and then stop and sleep for the other six, but he didn't stop until he reached the finish line. Although running at a slow pace, he simply didn't stop running, which helped him maintain the lead for the whole five and a half day. Upon being handed a $10,000 check as a prize for winning the race, Clif decided to keep none of it for himself and instead divided it evenly among the other five runners, who eventually managed to finish the race.

Cliff continued to run. In 1997,he set out to raise funds for homeless kids by running all 16,000 kilometers of the Australian coastline. In 2000,Cliff achieved a world age record in a six-day race in Victoria

Painting is an ancient medium and even with the introduction of photography, film and digital technology, it still has remained a persistent mode of expression. So many paintings have come into being over the years but only a small percentage of them could be described as "timeless classics". The following are some of the most famous paintings of all time. 

Leonardo Da Vinci, Mona Lisa, 1503—1519

Painted between 1503 and 1519, Leonardo da Vinci's attractive portrait has been a subject of controversy since the day it was made, due to two questions: Who's the subject and why is she smiling? A number of theories for the former have been provided over the years: That she's the wife of the Florentine merchant Francesco di Bartolomeo del Giocondo and that she's Leonardo's mother, Caterina. As for that famous smile, its quality has driven people crazy for hundreds of years. 

James Abbott McNeill Whistler. Arrangement in Grey and Black No. 1. 1871

Whistler's Mother, or Arrangement in Grey and Black No. 1, as it's actually titled, speaks to the artist's ambition to pursue art for art's sake. James Abbott McNeill Whistler painted the work in his London studio in 1871. Whistler's mother Anna is pictured as one of several elements locked into an arrangement of right angles. Her severe expression fits in with the rigidity of the composition, and it's somewhat ironic to note that despite Whistler's formalist intentions, the painting became a symbol of motherhood. 

Jan van Eyck, The Arnolfini Portrait, 1434

As one of the most significant works produced during the Northern Renaissance, this composition is believed to be one of the first paintings finished in oils. It portrays an Italian merchant and a woman who may or may not be his bride. In 1934. the celebrated art historian Erwin Panofsky proposed that the painting is actually a wedding contract. What can be reliably said is that the piece used orthogonal perspective to create a sense of space. It feels like a painting you could step into. 

Most of us have an unclear memory of learning about the Pythagorean Theorem (勾股定理) many years ago in math class. 

If you're anything like us writer-types, that 2, 000-year-old theorem went in one ear, and immediately out the other! But for two students at St. Mary's Academy in New Orleans, Louisiana, the theorem presented a challenge they simply couldn't resist taking on. As a reminder for those of us who aren't potential mathematicians, the Pythagorean Theorem is the basis of trigonometry (三角学). For over 2, 000 years, math scholars have stated it's impossible to use trigonometry to prove the Pythagorean Theorem because doing so would be circular logic. In other words, an idea cannot prove itself.

Calcea Johnson and Ne'Kiya Jackson have challenged that concept in their new abstract. The two high school seniors recently presented their abstract in front of the American Mathematical Society (AMS) at their annual southeastern conference. Unsurprisingly, they were the only teenagers there in a sea of math scholars! Their abstract states, "We present a new proof of the Pythagorean Theorem which is based on a fundamental result in trigonometry. " In plain English, that means Calcea and Ne'Kiya proved the theorem using trigonometry after all, and without using circular reasoning.

How did a pair of teenagers solve a riddle that has stumped so many mathematicians before them? Countless math scholars can do nothing facing this theorem. According to Calcea and Ne'Kiya, they have their teachers to thank!

The St. Mary's school slogan is "No Excellence Without Hard Labor", and they mean it! Both girls say their teachers push them to think outside the box and encourage them to discover new concepts. "We have really great teachers, " Ne'Kiya said with a smile. Calcea is proud of herself and her friend for doing something no other high school students have ever done.