1 . π (Pi) Day falls on March 14. This is the day when mathematicians and geometry (几何学) lovers around the world get together and celebrate the mathematical constant (常数) of Pi.

    1     Firstly, the date which can be represented numerically in the format 3.14 represents the first 3 digits of π. Besides, one of our greatest physicists Albert Einstein was born on March 14,1897. In 2018, the famous physicist Stephen Hawking passed away on Pi Day.

The earliest known celebration of Pi Day was organized by the physicist Larry Shaw at the San Francisco Exploratorium in 1988, featuring eating different kinds of fruit pies.     2     The museum staff marched around a circular room, sang songs, and ate pie. News stories about the celebration spread the idea to schools, museums, and communities. In 2009, US House of Representatives officially named this special day — “Pi Day”.

Many people celebrate Pi Day with family and friends.     3     People make pizzas (round ones, of course) and bake cream pies. Some people even use a special pie pan shaped like the Greek letter π. They are also willing to drink pi-neapple juice.     4    

Over thousands of years, people tried to unfold the puzzle behind this magic number. Before the appearance of modern computing technologies, mathematicians all over the world have made their efforts on calculating the approximation of Pi.     5     While Indian mathematician

Aryabhata approximated Pi to √￣9.8624 using the circumference of a polygon (多边形) with 384 sides. On 2019’s Pi Day, Google announced that the calculation of Pi has already reached 31.4 trillion decimal (小数的) places.

3 . Europe’s Most Beautiful Libraries

Libraries hold a special charm. Here’s a brief introduction of some of the most amazing libraries across Europe.

Built in 1999, it is an extension of the old library, whose terrace (露台) can accommodate large crowds for events such as concerts and plays. Apart from the main functions of a library, the building houses a bookshop, a cafe and a restaurant.

Located in the city center, it was founded in 1816, although the new building was completed in 1999. Its entrance contains blocks with writings in various languages, including a writing of Plato’s in Ancient Greek and also one in Ancient Polish.

Parts of the site were originally built in 1898, but the library was repaired following a fire in 2005. The innovative decoration gives the impression that they came from another planet. It also boasts the title of the biggest library in German-speaking countries.

It is located off San Marco Square and was completed in the late 1500s. Designed by Jacopo Sansovino, it has an elegant and somewhat unusual style for the period in which it was built. The interior beauty can really hold your breath.

4 . Rachel Beckwith was a 9-year-old girl from America. She had a special birthday _________. Instead of asking for presents, she dreamed of _________ $300 for “Charity: Water,” a group that helps bring clean water to people in developing countries. Rachel _________ to collect $220 from her family and friends, but she fell a bit short of her _________. She made a(an) _________ to her mom that she would try again next year.

Unfortunately, on July 20, 2011, Rachel was _________ in a car accident with her mom and sister. _________ her family only suffered minor injuries, Rachel was badly hurt and was _________ to the hospital. Three days later, her family had to make the _________ decision to take her off life support.

After Rachel’s passing, news of her birthday wish __________ worldwide. People started donating to “Charity: Water” in her __________, and the contributions poured in. Rachel’s heart was donated to a man in California, who also supported her __________.

By the end of Rachel’s birthday campaign (活动) in September, more than $1.26 million had been gifted to clean water projects. To __________ Rachel’s legacy (遗产), her family started a nonprofit called Rachel’s Wishing Well Foundation, __________ to spreading awareness about giving and helping others.

Anyone can make a big __________, no matter how small the contribution.

5 . Do you ever get that feeling that there aren’t enough hours in the day? That time is somehow racing away from you, and it is impossible to fit everything in. But then, you step outside into the countryside and suddenly everything seems slower, more relaxed, like time has somehow changed.

It’s not just you — recent research showed nature can regulate our sense of time. For many of us, the combined demands of work, home and family mean that we are always feeling like we don’t have enough time. Time poverty has also been exacerbated by digital technologies. Permanent (长久的，永久的) online connectivity lengthens working hours and can make it harder to switch off from the demands of friends· and family.

Recent researches suggest that the cure for our lack of time may lie in the natural world which may change how we experience time. These studies consistently showed that people report a sense of expanded time when they were in nature compared to when they were in an urban environment. For example, people are more likely to perceive (感知) a walk in the countryside as longer than a walk of the same length in the city. Nature seems to slow and expand our sense of time.

It’s not just our sense of time in the moment which appears to be changed but also our sense of the future. Spending time in nature helps to shift our focus from the immediate moment towards our future needs. So rather than focusing on the stress of the demands on our time, nature helps us to see the bigger picture. This can help us prioritise (优先处理) our actions to meet our long-term goals rather than living in a state of “just about keeping our head above water”.

Getting out into nature may sound like a simple fix, but for many people, particularly those living in urban areas, nature can be hard to access. Green infrastructure such as trees and parks in and around cities are essential to making sure the benefits of time in nature are accessible to everyone.

6 . A new observation in Sumatra caught seasoned scientists by surprise. An orangutan (红毛猩猩) known as Rakus treated a fresh wound with a medicinal plant, making this the first time an animal has been seen applying a biologically active substance (物质) for its health benefits. This leaves scientists wondering: Did humans invent medicine, or does it pre-date our species?

These animals are known to be among the most intelligent non-human primates (灵长类). They’ve been observed using tools, communicating vocally, and engaging in even more complex behaviors like calculated reciprocity, which involves aiding another orangutan with the expectation of being paid back. They can even use Skype with some help from humans.

Roughly 60,000-70,000 of these creatures remain in the wild, about 15,000 of which live on the Indonesian island of Sumatra. That’s where the Suaq Project, part of the Max Planck Institute for Animal Behavior, observes orangutans in their natural habitat.

The researchers noted in June that Rakus had a small wound on his face following a fight with another mature male orangutan. Several days later, Rakus did something no one had ever seen a primate do before. He began carefully picking the leaves from a climbing vine (藤蔓) known as akar   kuning. Local human populations have long used these leaves for pain relief and to treat conditions like malaria. Orangutans don’t usually eat these plants; indeed, Rakus didn’t eat them. He chewed (嚼碎) them and then applied the resulting paste to his facial wound.

This is the first time researchers have seen such behavior in 21 years at the Sumatran research station. Wild orangutans are rarely injured, so this may be a rare but widespread behavior. Or perhaps Rakus is the only one that knows this trick. The researchers assumed that early humans may have learned about certain treatment by observing animals engaging in similar behaviors. And here we are, thousands of generations later, still watching and wondering just how smart they are. Increasingly, it looks like orangutans are one cave painting away from civilization.

7 . Ellie Hamby, a documentary photographer, and Sandy Haze lip, a physician and lecturer, toured the world in 80 days, adventuring from the beaches of Bali to the deserts of Egypt.

The aged grandmothers started their ambitious adventure on January 11, according to the blog the two have used to document their travels. Their first stop was a location that escapes even many seasoned travelers: Antarctica. Getting to the southernmost continent first required crossing the Drake Passage, the known rough waters between the southern tip of South America and Antarctica’s South Shetland Islands. “For almost two days, we were a rocking and rolling and a slipping and sliding through the Drake Passage and we were holding on for dear life,” Hamby said in an interview with CNN. “It was just wild.” “But when we stepped foot on the ground on the Antarctic, you forgot all of that,” she recalled. “The beauty of the Antarctic is just unbelievable to see the penguins and the icebergs and the glacier — just, this was amazing.”

Since that first adventure, the pair have visited 18 countries across all seven continents, often dressed in matching T-shirts. They’ve also accumulated (积累) a loving social media following who track the “traveling grannies” on TikTok, Instagram, and Facebook.

Hazelip told CNN that she met Hamby after her husband died in 1999. The two bonded over their shared interest in travel and commitment to prioritizing unique experiences over comfort while abroad. Both became closer after Hamby’s husband died in 2005.

Hazelip says the idea for their trip originated a few years before they were each set to turn 80.

“I just got the idea because we had traveled previously together internationally,” she said. “And so about four years before we were going to turn 80, I mentioned to her one day, ‘Ellie, wouldn’t it be fun to go around the world in 80 days at age 80?’”

8 . One thing that many Americans can agree on, even in an era of deep political polarization (两极分化), is that our country is in a moral free fall. In survey after survey, US adults of all ages, education levels, political or religious backgrounds say that people are less kind, honest, generous, and respectful than they used to be. So is our nation’s moral foundation falling apart?

Not necessarily. In fact, two psychologists, Columbia’s Adam Mastroianni and Harvard’s Daniel Gilbert, say that the widespread belief in moral decline (下降) is a misconception. They recently conducted a meta-analysis of all the major surveys that asked Americans about the state of moral values in this country and they found that US residents have been complaining about one another’s declining morality for as long as researchers have been seeking their opinions on the matter. And yet when individual respondents are asked multiple times, over the span of a decade or more, to describe the level of politeness and kindness they observe in their fellow citizens, their descriptions of other people’s attitudes and behaviors do not actually worsen at all.

Mastroianni and Gilbert, whose paper appears in the journal Nature, say the results of similar surveys conducted in dozens of other countries over the decades suggest that people all over the world are easy to be influenced by the misconception that their peers are less moral than they once were. They say that this misconception is likely explained by two well-established psychological phenomena acting together: that we tend to pay closer attention to negative rather than positive information about people’s actions in the present day; and that we tend to selectively forget such negative impressions as the years roll on, leaving us with good memories for the past.

Mastroianni and Gilbert also say that their discovery has important social and political implications, especially given that, as one 2015 survey found, three-quarters of all Americans believe that addressing the moral breakdown of the country should be a high priority (优先项) for the government. “The United States faces many well-documented problems, from climate change and terrorism to racial injustice and economic inequality — and yet, nowadays it is believed that the government should devote fewer resources to reversing an imaginary trend.”

9 . Even though it’s never been easier to see the latest movies at home, there’s still nothing quite like watching a film in the dark of the cinema on the biggest screen possible.     1    There are a number of ways you can bring the cost down to make it more affordable, whether it’s an occasional treat or regular activity.

Avoid high-priced tickets

The most expensive tickets are going to be on peak times, which will usually run from Friday night until Sunday evening. But if you have the flexibility to go midweek or in the daytime you’ll hopefully find lower prices.     2     It’ll depend on which cinema you have near you.

Consider a membership

Some cinema memberships also offer free tickets and then discounts on future visits, so they’re worth looking at if you know you’ll make the money back. But if you are going at least twice a month then the all-you-can-watch memberships can be fantastic value. However, one disadvantage is that if you want to see a film at a different chain you’ll be paying again.     3    

Use discounted gift cards

    4     Or you can use cashback apps like Jam Doughnut and Hyper Jar to buy the gift cards and get a percentage back. What’s good about these is that they stack with other offers, such as Meerkat Movies and silver screenings, so you save twice.

    5    

Finally, armed with your cheap cinema tickets, don’t ruin all your good work by buying the popcorn at the cinema. The price is always high. But it can be easily avoided by hitting a supermarket beforehand to buy much cheaper treats. You don’t need to secretly take them in because all the big cinemas allow you to do this.