《工程硕士研究生英语基础教程unit3.ppt

Ozone depletion describes two distinct, but related observations: a slow, steady decline of about 4 percent per decade in the total volume of ozone in Earths stratosphere (the ozone layer) since the late 1970s, and a much larger, but seasonal, decrease in stratospheric ozone over Earths polar regions during the same period. The latter phenomenon is commonly referred to as the ozone hole. In addition to this well-known stratospheric ozone depletion, there are also tropospheric ozone depletion events, which occur near the surface in polar regions during spring Zimbabwe is a landlocked country located in the southern part of the continent of Africa, between the Zambezi and Limpopo rivers. It is bordered by South Africa to the south, Botswana to the southwest, Zambia to the northwest and Mozambique to the east. Zimbabwe has three official languages: English, Shona (a Bantu language), and Ndebele (also a Bantu language). Peru officially the Republic of Peru is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean. II. Language Points 1. Despite decades of scientific research, no one yet knows how much damage human activity is doing to the environment. despite: notwithstanding; in spite of; regardless prep.不管, 不顾, 尽管 e.g. He came to the meeting despite his illness. 尽管生病，他还是来参加会议。 Despite all our efforts we still lost the game. 尽管我们尽了全力，我们还是输掉了比赛。 Useful expression: in spite of 不管, 尽管, 任凭 despite 不管, 尽管, 任凭 decades of: years of/miles of 数十，几十年 useful expression: a couple of decades二三十年 2.what is not in doubt, however, is devastating effect humans are having on the animal and plant life of planet. “what is not in doubt, … of the planet.”: Nobody would suspect, however, that humans are having ruinous effect on th