Directions: For this part， you are allowed 30 minutes to write a composition based on the following graph showing the growth of the world's The opening sentence is given and you are required to develop it into a full Your part of writing should be no less than 120 Some useful words and phrases are provided， but you do not have to include all of (Suggested words and phrases: birth control， death rate， population explosion， food shortage)The Problem of Human Population It has been estimated that a thousand years ago there were less than 400 million people on Today， however， the world's population has amounted to 5，000 What is worse， it keeps growing at a surprising If this trend continues， the world's population will shoot up to 7，000 million by the year This is what we call population The rapid development of science and technology is the main cause of population We can see that the population has been growing at a tremendous speed since the Industrial and Agriculture Revolution in 1650， which raised the people's standard of living， and the emergence of modern medicine in 1550， which lowered the people's death Population explosion will result in a lot of such problems as food shortage， housing shortage and It is time that we acted quickly to carry out the policy of birth control otherwise， man's survival on the earth will be 你再改改就应该没问题了
Water pollutionWater pollution is a major problem in the global It has been suggested that it is the leading worldwide cause of deaths and diseases， and that it accounts for the deaths of more than 14，000 people An estimated 700 million Indians have no access to a proper toilet， and 1，000 Indian children die of diarrheal sickness every Some 90% of China's cities suffer from some degree of water pollution， and nearly 500 million people lack access to safe drinking In addition to the acute problems of water pollution in developing countries， industrialized countries continue to struggle with pollution problems as In the most recent national report on water quality in the United States， 45 percent of assessed stream miles， 47 percent of assessed lake acres， and 32 percent of assessed bay and estuarine square miles were classified as pollutedWater is typically referred to as polluted when it is impaired by anthropogenic contaminants and either does not support a human use， like serving as drinking water， and/or undergoes a marked shift in its ability to support its constituent biotic communities， such as Natural phenomena such as volcanoes， algae blooms， storms， and earthquakes also cause major changes in water quality and the ecological status of Causes of water pollutionThe specific contaminants leading to pollution in water include a wide spectrum of chemicals， pathogens， and physical or sensory changes such as elevated temperature and While many of the chemicals and substances that are regulated may be naturally occurring (calcium， sodium， iron， manganese， ) the concentration is often the key in determining what is a natural component of water， and what is a Oxygen-depleting substances may be natural materials， such as plant matter ( leaves and grass) as well as man-made Other natural and anthropogenic substances may cause turbidity (cloudiness) which blocks light and disrupts plant growth， and clogs the gills of some fish Many of the chemical substances are Pathogens can produce waterborne diseases in either human or animal Alteration of water's physical chemistry includes acidity (change in pH)， electrical conductivity， temperature， and Eutrophication is an increase in the concentration of chemical nutrients in an ecosystem to an extent that increases in the primary productivity of the Depending on the degree of eutrophication， subsequent negative environmental effects such as anoxia (oxygen depletion) and severe reductions in water quality may occur， affecting fish and other animal
写作思路：从描述环境污染的坏处的写作目的、中心主旨入手，以使文章中心思想鲜明、深刻地表现出来，正文：As we all know， pollution is very harmful to living In this world， there are many different types of 我们都知道，污染对生物有很大危害。在这个世界上，有许多不同类型的污染。For example， water pollution， air pollution， noise pollution， Water pollution will make people sick and even die， and dirty air will increase the probability of lung 例如：水污染、空气污染、噪音污染等等、水污染会使人们生病，甚至死亡、脏空气会使患肺癌的几率上升。And noise pollution can cause People's health level will 而噪音污染会让人失眠。人们的健康水平会下降。In my opinion， people should take measures to protect the Recently， not only government departments but also individuals have taken part in environmental 在我看来，人们应该采取措施去保护环境，最近，不仅仅是政府部门，个人也参与到环保中去。This is a good The river is clean， the air is fresh， and people are aware of the importance of environmental 这是个好现象，河流干净了，空气清新了，人们也意识到环保的重要性。
The water resources is short and pollution already threaten seriously our country's survival and The Baoding city is one of national most serious water scarcity This article through carries on the sample investigation to the Baoding moat rivers section， and carries on the crucial target with the related measuring technique the survey， refers to the surface water pollution control standard to judge the rivers whether to be polluted， and proposes the corresponding processing
