高二上英语动词的时态

Reading materials: 1-1 "biosphere 2"

"Biosphere 2" (Biosphere 2) built in the desert of Arizona in the United States, its name is the earth as a Biosphere 1 ". Biosphere 2 is a simulation of artificial building ecological environment of the earth totally enclosed experiment field, also some people call it "tiny earth", or "prototype" Mars colony. This covers an area of 13000 square meters, eight storeys high dome shape sealing glass steel structure buildings, is people spent nearly $200 million and nine years to build up, the purpose of the experiment is to investigate human left earth biosphere 1 "" if I can survive. In this miniature world, there are Marine, plains, swamp, forest, desert, agriculture and human settlement, is a self-contained small ecosystem. "Biosphere 2" although isolated, but can be by power transmission, telecommunications and computer and external contact. Staff in biosphere 2 "" you can watch TV, can through radio contact with relatives and friends.

In January 1991, eight scientists into the "biosphere 2". Scientists have planned to send staff to live in "biosphere 2" for two years, the human live on other planets to establish base for the future to explore. More than a year later, however, the "biosphere 2" ecological status plummet, oxygen (O2) content drops rapidly from 21% to 21%, and carbon dioxide (CO2) and the content of nitrogen dioxide (NO2) has soared, the atmosphere and water acidification, many species die, and the used to absorb CO2 morning glory is growing. Most vertebrates death, all the pollinators of death caused by pollen propagation and breeding of plants all died. Because of the rain is out of control, artificial into a jungle and desert grassland. "Biosphere 2" the deterioration of the air inside directly endanger the health of the residents, the scientists were forced to withdraw in advance the "garden of Eden". "Biosphere 2" the experiment ended in failure.

Over the years, the human dream to dream out of the earth, into the universe. With the deterioration of the earth's environment, this desire seems to have added the colour of fleeing, people of endeavour, accelerated the pace of seeking "Noah's ark". Maybe "biosphere 2" on the error or equipment failure has the technology, maybe people in the future will be to no. 3 "biosphere", 4 "biosphere" challenge. However, from "biosphere 2" failure reflected the deep information far more ruthless than itself. It proves: like intangible, big YinXi sound. The earth's environment is formed after billions of years of ups and downs, the structure of this abnormal reliable, people eager to glimpse its context, nearly as well, but it is by no means simply artificial imitation reengineering can finish.

"Biosphere 2 failure warned us:" the human in the boundless universe is only the earth in their homes, fled and were are with enough. The earth is not laboratory, we can't afford to lose, only we treat and protect it is the real way out.

Similarly, the coast of northern Japan in aomori village built six similar "mini" earth, covers an area of only 4700 m2, is three stadium style buildings are connected by a corridor of stainless steel.

A complete set of facilities at a cost of $6500, built in 2000, researchers have begun preliminary tests at the moment. After the official start of the test there will be two scientists into the plants and animals and the air of the building is fully enclosed, a week at first, and then gradually extended to five months. Test purpose is to simulate a closed space within the oxygen and carbon dioxide cycle between plants, humans and animals.

Quoting from: Peng Lili lead, environmental memo of the 20th century, Beijing: huaxia press, 2001, 6: p107; Fang ji, Meng Zhehong, Wang Yanjin, environmental education resource base, Beijing: huaxia publishing house.