In 1916 the United States started the world's first national park system. Since then, it     1    （serve）as a model for other countries that try to better protect the environment and let people enjoy nature.

A national park is a reserve of land    2    declare) and owned by the government, protected from human development and pollution. Now China is planning its own national parks system. On Dec 5, China passed two pilot plans for national parks    3    (protect) the giant panda, Siberian tiger and Amur leopard.

But national parks are not only for animals. In mid-2015, China started to build pilot national parks in nine provinces.     4    most famous one is the Sanjiangyuan national park on the Qinghai-Tibet Plateau. It aims to protect China’s water source. Sanjiangyuan, or “Source of Three Rivers”, is     5    the Yellow, Yangtze, and Lancang rivers start.

Before this national park project, China had set     6    thousands of nature parks, forests and scenic areas as protected areas. However, they haven’t been managed well     7    too many different organizations have been involved in the protection of the different areas, according to the China Daily.Under the new plan, national parks will cover big areas and include different protected areas.

For example, the habitats of wild pandas lie in different provinces and     8    (cut) into even smaller pieces by railways, roads and power lines. This makes isolated panda groups more open to     9    (dangerous). The panda national park will cover all the habitats and make the protection of animals as comprehensive as possible.

But this increased protection doesn’t mean national parks will shut their doors to humans. Instead, the new system will offer people a chance to     10    (deep) feel nature.

What defines a healthy city Is it a place with a lot of open spaces    1    people can exercise and enjoy the fresh air .A place with little or no pollution .A place in which people can     2    (free) socialize and express their ideas Perhaps, it’s all that plus more. Other considerations are the availability of health and fitness facilities, an excellent healthcare program and sincere efforts by    3    local government to actively promote health and wellness among its citizens. Of all the cities in the world, one of the top six     4     (healthy) cities is Copenhagen, Denmark.

Copenhageners love to walk. Foot traffic accounts    5    80% of all traffic in the Copenhagen city center. Those who prefer can also bike. It is estimated that more than a third of all work trips in Copenhagen    6    (carry) out on a bike. As for the climate here, the city does not have the blessing of pleasant weather all year round.    7    everything starts to freeze, it turns several city squares into huge skating fields. The frozen parts of the city also make    8    easier for residents to skate around. The city also has museums and art galleries for the kids and    9    (grown-up). It has the Royal Danish Academy of Fine Art and the Royal Library housed in a rather grand building    10    (call) the Black Diamond.