1 . A national park is an area set aside by a government for the preservation of the natural environment. The national parks in the United States and Canada center on the protection of both land and wildlife.     1     And those in Africa primarily protect animals.

It is widely thought that the idea of a park or nature reserve under state ownership started in the United States in 1870.     2     Yosemite, Sequoia, and General Grant National Parks were established in the United States in 1890. And the U. S. National Park Service (NPS)was created in 1916 to manage the parks.     3     In addition to national parks, the system included national preserves, seashores, historic parks and sites and so on.

Partly following the American example, movements supporting national parks sprang up in many other countries.     4     . And Canada set up its first three national parks in the mid-1880s. The establishment of modern national parks and nature reserves gained momentum (动力)only after World War I or, in some cases, after World War II in Europe. Great Britain established the administrative machinery for both national parks and nature reserves in 1949.     5    

But interest in parks came later in Asia and Latin America than it did in the Anglo-American countries and Europe.

When the Library Cave, known as Cave 17 from the Mogao Cave Complex at Dunhuang, China, was opened in 1900, several tons of manuscripts, scrolls, booklets and paintings on silk and paper     1    (find) literally stuffed into it. These     2    (value) writings were collected between the 9h and 10 centuries CE, by Tang and Song Dynasty Buddhist monks     3     carved out the cave and then filled it with ancient and current manuscripts on topics     4    (range) from religion and philosophy, history and mathematics, to folk songs and dance.

Cave 17 is only one of the 735 human-made caves     5    (call) Mogao Grottoes, which were dug into a loess cliff about 15 miles southeast of the town of Dunhuang in Gansu Province. Dunhuang’s long and glorious history reflects its     6    ( significant) as a center of cultural and religious exchange. These caves were dug and maintained by Buddhist monks from 366 CE and were sealed and hidden about a thousand years ago. It was not until 1900       7    , they were rediscovered.

The Dunhuang Academy was set up in China in     8     1980s, aiming to collect and preserve the manuscripts; the International Dunhuang Project (IDP) was formed in 1994     9    (bring) the international scholars together to work jointly on the     10    (collection). The IDP has put many of the documents online, as images and as translations.

It seems inhuman to care more about a building than about people. That the sight of the Notre Dame's     1    (go)up in flames has attracted more attention than floods in southern Africa which killed over 1,000 has aroused understandable feelings of guilt. Yet the widespread sorrow is     2    (definite)human—and in a particularly 21st-century way.

It is not just the economy that is       3    (globe)today, it is culture too. People wander the world in search not just of jobs and       4    (secure)but also of beauty and history. Familiarity breeds affection. A building     5     whose sunny steps you have rested or in front of which you       6    (take)a selfie with your loved one, becomes a warm part of your memory. That helps explain why the whole world is in deep sorrow.

However, the emotions are less about the building itself than about     7     losing it might mean. Notre Dame is an expression of humanity, having experienced 850 years of political turbulence(动荡)—through war, revolution and Nazi occupation.

And it will be rebuilt. It will never be the same, but that is as it should be.     8     Victor Hugo wrote in The Hunchback of Notre Dame,     9     three-volume love-letter to the cathedral: “Great buildings are the work of centuries. Art     10    (transform)as it is being made. Time is the architect; the nation is the builder.”