【推荐1】If there is a building which symbolizes a country—such as the Eiffel Tower for France and Sydney Opera House for Australia—then it has to be the Taj Mahal for India.

It was set up by Emperor Shah Jahan in 1653 in memory of his wife, Mumtaz Mahal. From the time they got married, they wouldn’t be separated. She followed him to wars, advised him on affairs of state, and was loved by his people for her good work. But she died in 1631 during childbirth. The emperor was heartbroken and had the Taj Mahal built as a sign of his love.

It took more than 20 years for the Taj Mahal to be built. Workers were brought in, not only from all over India, but from Central Asia too. A total of 20,000 people worked on the building.

In 1657, Shah Jahan fell ill, and in 1658 his son Aurangzeb, imprisoned (囚禁) his father and seized power. Shah Jahan stayed in prison until his death in 1666. He was finally buried there with his wife he could never forget.

The Taj Mahal is definitely worth more than a single visit. As it is built with white marble stones, its character changes in different lights. It looks more beautiful at sunrise and sunset. At sunset, for example, the color of the Taj changes from white to yellow, then to pink. As the moon rises, it turns a silvery white.

To show respect to the Taj, tourists are asked to take off their shoes during their visit.

【推荐2】Candy comes in many flavors. Some taste like fruit. Some taste like flowers. Some are chewy, like taffy (太妃糖) and gum. Hard candies are, well, hard! So, they last a long time.

But, in spoken English, there are some types of candy that you cannot eat. For example, you can’t eat eye candy. Eye candy is a person-man or woman-who is very good-looking. So, looking at this person is a treat for the eye, just like candy is a treat for the taste buds.

Do you hear of candy coat? Of course it is not a coat made of candy. But you can say I don’t candy coat the truth. What does candy-coating something mean? Well, some pills are covered with a coat of thin, sweet candy. The coating makes swallowing the pill easier, and it may hide a bad taste. So, candy coating a difficult truth or situation means you don’t directly discuss its bad parts.

After talking about candy you may want to eat some candies. However, some people dislike things that are very sweet, especially adults. But even if you do not like candy, you can still be called a kid in a candy store. This expression means a person is very happy to do something or to simply be somewhere. Imagine a child going from one candy display to the next, not knowing which candy to choose!

Talking about children brings us to another expression: as easy as taking candy from a baby. Think about a small, helpless baby holding a piece of candy. Taking it would be very easy—mean, but easy. So, use this expression when you are talking about something that may be simple to do, but probably not right.

【推荐3】When the UNESCO World Heritage Committee(WHC) met from July 16 to 31, 2021, they were tasked with addressing threats to some of the world's most treasured sites of priceless natural and cultural heritage. Among the issues the committee must face is the growing threat that dams cause to some of the world's most treasured World Heritage Sites.

A recent study found that over 500 dams under construction or planned worldwide would be built in protected areas. while dams threaten at least 80 World Heritage Sites. This number is only expected to grow as dam developers, faced with a reduction in the number of dam sites available, pursue increasingly reckless(不计后果的) projects such as the Batang Toru Dam, which experts say could lead to the extinction of the newly discovered Tapanuli orangutan(红毛猩猩).

The increasing impact of dams on World Heritage Sites has caused a global outcry, most recently in the case of the Selous Game Reserve, a World Heritage Site recognized as a biodiversity hotspot and one of the largest protected areas for African wildlife. The Tanzanian government's decision to construct the Julius Nyerere Dam in the Selous led to an angry proposal from UNESCO to remove it from the list altogether.

Meanwhile, history is in danger of repeating itself in Laos, where the planned Luang Prabang dam threatens the historic city it's named for. Luang Prabang, the old royal capital was listed as a World Heritage Site in 1995. Despite this World Heritage status, the Mekong River, which flows through and is an important part of Luang Prabang's history. culture, and way of life. is under threat. The Laos' government is planning to build a dam, 25 kilometers upstream from Luang Prabang. Given the proposed dam's size and locntion, the dam will have major environmental impacts on the river system and surrounding area.

【推荐1】Born in Potsdam (in the Kingdom of Prussia) in 1821, Helmholtz was one of the 19^th century’s most knowledgeable scientists, whose name turns up in the history of multiple scientific fields and specialties. As a youngster, he had an interest in physics, but that seemed a financially unwise career choice. He went to medical school and studied physiology instead, because he was drawn to others who promoted the point that physiology should be based on the principles of chemistry and physics, not the vital forces that had been popularly emphasized previously.

After earning his medical degree, Helmholtz served as an army surgeon before becoming professor of physiology at the University of Konigsberg. During that time, he composed a groundbreaking paper on the conservation of energy, which made him a good reputation in science community. His main argument is that all science can be reduced to mechanics. It is emphasized that Newtonian mechanics and Lagrangian mechanics are mathematically equivalent, so a force can be measured by the Laplace method in terms of the energy transferred by the force or the work done by the force. All of this energy is conserved. While at Konigsberg, he studied the nervous system, optics (光学) and acoustics (声学), especially with regard to the physiology of the senses. Then he moved on to the University of Bonn as professor of anatomy (解剖学) and physiology.

After some time at the University of Heidelberg, where he became interested in philosophy, in 1871 he was awarded the physics chair at the University of Berlin. At last he could focus on physics, emphasizing the importance of the principle of least action for explaining physical phenomena. He also explored the branches of Maxwell’s new theory. By this time, he was recognized as one of Germany’s premier scientists, until his death in 1894.