First listen and then answer the following question.
听录音，然后回答以下问题。
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Contamination of water supplies is usually due to poor sanitation close to water sources, sewage disposal into the sources themselves, leakage of sewage into distribution systems or contamination with industrial or farm waste. Even if a piped water supply is safe at its source, it is not always safe by the time it reaches the tap. Intermittent tap-water supplies should be regarded as particularly suspect.
Travellers on short trips to areas with water supplies of uncertain quality should avoid drinking tap-water, or untreated water from any other source. It is best to hot drinks, bottled or canned drinks of well-known brand names -- international standards of water treatment are usually followed at bottling plants. Carbonated drinks are acidic, and slightly safer. Make sure that all bottles are opened in your presence, and that their rims are clean and dry.
Boiling is always a good way of treating water. Some hotels supply boiled water on request and this can be used for drinking, or for brushing teeth. Portable boiling elements that can boil small quantities of water are useful when the right voltage of electricity is available. Refuse politely any cold drink from an unknown source.
Ice is only as safe as the water from which it is made, and should not be put in drinks unless it is known to be safe. Drink can be cooled by placing them on ice tather than adding ice to them.
Alcohol may be a medical disinfectant, but should not be relied upon to sterilize water. Ethanol is more effective at a concentration of 50-70 per cent; below 20 per cent, its bactericidal action is negligible. Spirits labelled 95 proof contain only about 47 per cent alcohol. Beware of methylated alcohol, which is very poisonous, and should never be added to drinking water.
If no other safe supply can be obtained, tap water that is too hot to touch can be left to cool and is generally safe to drink. Those planning a trip to remote areas, or intending to live in countries where drinking water is not readily available, should know about the various possible methods for making water safe.（RICHARD DAWOOD Travellers' Health）
New words and expressions 生词和短语
contamination
n. 污染
sanitation
n. 卫生，卫生设备
sewage
n. 污水
leakage
n. 泄漏
intermittent
adj. 间歇的，断断续续的
carbonated
adj. 碳化的，碳酸的
acidic
adj. 酸的，酸性的
alcohol
n. 酒精
disinfectant
n. 消毒剂
sterilize
v. 消毒
ethanol
n. 乙醇
bactericidal
adj. 杀菌的
negligible
adj. 可以忽略的，微不足道的
methylated
adj. 加入甲醇的
以下为人工智能创作
指令1：请根据标题Water and the traveller，写一篇英语文章，达到英语4级水平，四段，共1500字内。
回应：
Title: Water and the Traveler
Introduction:Water is an essential element for all forms of life, including humans. It is a basic necessity that we cannot live without. For travelers, water plays an even more crucial role as they are often exposed to different environments and situations where access to clean and safe drinking water may be limited or uncertain. In this article, we will discuss the importance of water for travelers and how they can ensure they have enough supply during their journeys.
Body Paragraph 1:The first thing that comes to mind when thinking about water and travelers is hydration. Dehydration can lead to various health problems such as headaches, dizziness, fatigue, and even heatstroke in extreme cases. Travelers need to stay properly hydrated throughout their journey to maintain their energy levels and avoid any potential health issues. This means carrying enough water with them at all times and replenishing it regularly. However, carrying large amounts of water can be cumbersome and impractical, especially for long-distance travelers. Therefore, it is important for travelers to plan ahead and research their route to find places where they can refill their water bottles safely.
Body Paragraph 2:Another aspect of water and travelers is hygiene. Access to clean water is not only necessary for drinking but also for maintaining personal hygiene. Washing hands before meals, after using the restroom, or after being in contact with animals or dirty surfaces can prevent the spread of germs and reduce the risk of infections. Travelers should always carry hand sanitizer or soap with them and make sure to wash their hands frequently. Additionally, if possible, they should try to take showers or baths regularly to keep themselves clean and refreshed.
Body Paragraph 3:Water can also be a source of adventure for travelers. Many popular tourist destinations offer activities such as swimming, snorkeling, diving, kayaking, and rafting that involve being in or on the water. These activities can provide unique experiences and memories that last a lifetime. However, safety should always be a top priority when engaging in these activities. Travelers should follow proper safety guidelines and equipment recommendations provided by professionals and never underestimate the power of water. Drowning accidents can happen quickly and unexpectedly, so it is essential to be aware of one's limits and abilities.
Conclusion:In conclusion, water plays a vital role in the lives of travelers. It is essential for hydration, hygiene, and adventure. By planning ahead and taking necessary precautions, travelers can ensure they have enough supply of clean and safe drinking water during their journeys. They should also prioritize personal hygiene practices and follow safety guidelines when participating in water-related activities. With proper preparation and awareness, travelers can enjoy their trips while staying healthy and safe. Remember, water is not just a beverage; it is a fundamental element that sustains life itself.
指令2：请根据该段，用英文续写三段，800字以内。所给段落如下：Contamination of water supplies is usually due to poor sanitation close to water sources, sewage disposal into the sources themselves, leakage of sewage into distribution systems or contamination with industrial or farm waste. Even if a piped water supply is safe at its source, it is not always safe by the time it reaches the tap. Intermittent tap-water supplies should be regarded as particularly suspect.
回应：
Paragraph 1:
The contamination of water supplies is a critical issue that affects millions of people worldwide. It can lead to various health problems, including diarrhea, cholera, and dysentery. In many cases, the contamination occurs due to poor sanitation practices close to water sources. For instance, if people defecate or dispose of sewage near rivers or streams, it can easily contaminate the water supply. Additionally, leakage of sewage into distribution systems or contamination with industrial or farm waste can also result in unsafe drinking water.
Paragraph 2:
Even if a piped water supply is safe at its source, it may not remain so by the time it reaches the tap. This is particularly true in areas with intermittent tap-water supplies. When the water supply is interrupted, it creates an opportunity for contaminants to enter the system. For example, during periods of low pressure or no flow, contaminated groundwater can seep into the pipes through cracks or other openings. Furthermore, when the water supply resumes, it can flush out any accumulated contaminants and distribute them throughout the system.
Paragraph 3:
To address this issue, governments and organizations must take steps to improve sanitation practices and protect water sources from contamination. This includes investing in infrastructure such as sewage treatment plants and implementing regulations to prevent industrial and agricultural pollution. Additionally, regular monitoring and testing of water quality are essential to ensure that drinking water remains safe for consumption. In areas with intermittent tap-water supplies, it may be necessary to provide alternative sources of safe drinking water, such as bottled water or water purification systems. By taking these measures, we can help ensure that everyone has access to clean and safe drinking water, which is essential for good health and well-being.
