An ancient culture dating back more than 5,000 years proved China’s early exchanges with other societies, experts say.

Experts believe the Majiayao culture had a close     1    (connect) with other various cultures. They put it forward at a recent meeting     2     was held in Gansu Province. With more than 5,000 years of history, it plays an important role in the development of the Chinese civilization (文明). This culture spread to Central Asia through     3     is now China’s Xinjiang Province,     4    (bring) rice from China to the west.

Swedish expert Johan first     5    (investigate) cultural sites in 1924. In the 1940s, Xia Nai named the sites after the Majiayao, with painted pottery (彩陶) as     6    (it) most special feature. Some experts point out that the Majiayao culture     7    (obvious) shares similarities with the cultures of some parts of the Black Sea. People from these cultures used pottery     8    (make) human head sculptures.     9     addition, some Central Asian features also appeared on the painted pottery of the Majiayao.

Actions     10    (take) to protect the Majiayao culture by building museums, organizing meetings and doing more research so far.

3 . As of 2020, the world's biggest lithium-ion (锂离子) battery is hooked up to the Southern California power grid and can provide 250 million watts of power, or enough to power about 250,000 homes. But it's actually not the biggest battery in the world: these lakes are.

Wait - how can a pair of lakes be a battery? To answer that question, it helps to define a battery: it's simply something that stores energy and releases it on demand. The lithium-ion batteries that power our phones, laptops, and cars are just one type. They store energy in lithium ions.

How do the two lakes store and release energy? First, one is 300 meters higher than the other. Electricity power pumps that move billions of liters of water from the lower lake to the higher one. This stores the energy by giving the water extra gravitational potential energy. Then, when there's high demand for electricity, valves (阀门) open, releasing the stored energy by letting water flow downhill to power 6 giant turbines that can generate 3 billion watts of power for 10 hours.

Unfortunately, neither of the giant batteries we've talked about so far is big enough to power multiple cities. The two lakes setup requires specific geography, takes up a lot of land, and has high upfront costs to build. The giant lithium-ion battery in California can power about 250,000 homes, yes, but only for an hour. Lithium-ion batteries also require certain heavy metals to make. These resources are limited, and mining them causes environmental damage. Inventors all over the world are rising to the challenge of making batteries that can meet our needs - many of them even weirder than the two lakes.

4 . Rules for proper gift giving

When you are planning to give a gift, it is important to think about the receiver. As the gift is for the other person, it should be suitable for his or her particular personality. Is he or she a family member or a close friend?    1    These are valuable things to keep in mind when choosing the right gift for someone.

At a dinner party, it is usually proper to show up with some sort of gratitude(感谢) for the host.     2     This type of gift does not have to be expensive. It just needs to be something that can serve as a sign of appreciation. This can be done in the form of flowers or a bottle of wine.

When someone gives you a gift, you generally want to give one in return.     3     There are situations where people give gifts and do not expect anything in return. This occurs when you are celebrating your birthday or graduation. If you receive gifts from your friends, then just a thank-you note will be enough.

When in a situation where you have received something expensive and are expected to give one in return, many people feel pressured to give a gift of greater or equal value to the one that was gifted to them. However, it is important to distance yourself from these assumptions.     4    

Well, what should you do when you have forgotten to send a gift? It happens to all of us. Whether it is a family member’s birthday or a friend’s graduation ceremony, forgetting to give a gift is awkward. So, it can be difficult to find the right way to make up for forgetfulness. However, before you begin to panic, know that a late gift is better than no gift.     5    

6 . Watching a young, 21-year-old Jordan Spieth win the US Masters today, I could not help but think of the great qualities he displayed to win the most famous golf event on the calendar against the greatest players in the world.

Jordan Spieth has learned to keep himself in check. There is a great proverb: “A fool shares all his or her feelings while a wise man keeps them in check.” As I watched Spieth playing, I noticed a constant calm around him. Whether he hit the shot he wanted or not, he was the same and kept his emotions steady (稳定的) and strong. He never blamed the crowd, clubs or wind.

He knows which club he is going to drive with on every hole; he knows which side of the fairway (高尔夫球道) to land and exactly where he wants to be standing on every green when he is putting; he has played it through his minds for months. He is the person who makes things happen by planning in advance. Winning is not a fluke (侥幸击中); it’s a by-product of months and years of planning. Nothing happens by chance.

If there is an event that every golfer dreams of winning, it’s the US Masters. So, how would Spieth have felt in 2014 getting so close to winning but coming second? As good as second was, he only wanted to be first. The difference between great shots and poor shots at the Masters is only inches. In that 2014 final round, Spieth was standing on the 8th hole with a 2-shot lead, but through a number of small misses he lost it and never recovered it. However, he never stops learning. As a great person once said, “While you’re green, you’re growing; when you’re brown, you’re dying.” He stays green. He is always reading, learning, and he understands that the greatest teacher of all is failure.

Chinese scientist Yuan Longping, known     1     developing the first hybrid rice strain that pulled countless people out of     2     （hungry）, died of illness at 91 on Saturday. "Father of hybrid rice", the top rice scientist in China, Yuan Longping passed     3     at 13：07 pm in a hospital in Changsha of Hunan province. Family members hummed songs to Yuan in     4     final hours, reporters at the site said.

    5     （spend）over five decades in hybrid rice research, the academician with the Chinese Academy of Engineering（中国工程院院士）has helped China work     6     great wonder, feeding nearly one-fifth of the world's population with less than 9 percent of the world's total land.

    7     impresses people most about Yuan Longping is his ongoing ability to fulfil his dreams. On China's Twitter-like Sina Weibo, the news     8     （view）more than a billion times so far, with netizens from all walks of life     9     （express）grief at the death of the great man. "Three times a day, when we enjoy the fragrance of rice, you will be dearly remembered." said a comment     10     has been liked more than 600,000 times.

10 . Football scarves, shirts and...eggshell art？A retired schoolteacher is making mascot memorabilia(吉祥物纪念品) from eggshell, skillfully crafted by hand.

Nguyen Thanh Tam, 67 years old, spends hours every day making the models. He is driven by his soccer enthusiasm shared by millions across Vietnam glued to the World Cup.

The soccer tournament kicked off in Russia a few weeks ago. Most of his tiny statues are of the tournament mascot, a wolf named Zabivaka. The wolf wears big sports glasses and is kicking a soccer ball. Tam also has plans for models of soccer heroes Cristiano Ronaldo and Lionel Messi.

Though not widespread in Vietnam, using eggshell in art is not unheard of. Traditional fine works often feature in laid eggshell that is used to replace white paint.

Tam first developed the unique hobby around New Year in 2002. He was looking for the right material to make a statue with his 13­year­old students. He discovered that an eggshell perfectly displayed Saint Nick's round belly. He eventually married his passion(酷爱) for crafts and soccer. He started making World Cup mascots during the 2010 World Cup in South Africa.

Now he has about 1, 000 of the small statues in his apartment. Some celebrate the 2016 Rio Olympics and the Euro 2016 football tournament in France. Others are of celebrities like Charlie Chaplin, Barack Obama and Gangnam Style's PSY. He also does birds and animals. He has his pig­related series to mark the Year of the Pig in 2019.

Tam says the biggest challenge is to find the right egg shape to fit the creation, so he has expanded beyond chicken eggs to include ostrich(鸵鸟) and quail(鹌鹑) eggs. He has also widened his egg artworks by using up all the yolks(蛋黄) and whites he used to throw away.

Tam doesn't sell the delicate dolls, preferring instead to keep them on display to impress his visitors. He has already received a nod from Vietnam's record center for the most eggshell art created, but he has a global ambition.“I hope one day my eggshell art will be recognized as a world record, ”he said with a smile.