新概念美音版第四冊 Lesson 38 Water and the traveller 水和旅行者

 
Lesson 38   Water and the traveller 水和旅行者 
    
First listen and then answer the following question.
 
聽錄音，然後回答以下問題。

What does this text describe?

    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 生詞和短語
 
    contamination
n.   汙染
    sanitation
n.  衛生，衛生設備
    sewage
n.  汙水
    leakage
n.  泄漏
    intermittent
adj. 間歇的，斷斷續續的
    carbonated
adj.  碳化的，碳酸的
    acidic
adj. 酸的，酸性的
    alcohol
n.  酒精
    disinfectant
n.  消毒劑
    sterilize
v.  消毒
    ethanol
n.  乙醇
    bactericidal
adj. 殺菌的
    negligible
adj. 可以忽略的，微不足道的
    methylated
adj. 加入甲醇的
  
參考譯文
 
    水源的汙染通常是由於接近水源的地方衛條件太差而造成的：汙水排入水源，汙水滲入給水係統或工農業汙水造成汙染。即使管道供水係統在水源處安全的，等水到達龍頭時就不一定總是安全的了。斷斷續續的水管應該被視為是非常可疑的。
 
    短途旅行到水質不保險的地區時，應避免飲用水龍頭的水或未經處理任何其他來源的水。最好僅飲用開水，名牌瓶裝或罐裝水 -- 裝瓶廠通常遵循國際水處理的標準。碳酸飲料是酸性的，就更安全一些。確保瓶子是當你麵開啟的，瓶口清潔幹燥。
 
    燒開一直是水處理的一種好辦法。有的酒店根據要求可提供開水，這些開水可用於飲用和刷牙。如果有相配的電壓，可以煮少量水的便攜式熱水裝置是有用的。應謝絕任何不明來源的冷飲。
 
    冰塊隻有當製造冰塊的水安全時才是保險的，隻有知道冰塊安全時才能加入飲料。可以把飲料置於冰塊之上來冷卻，而不是把冰塊加進飲料之中。
 
    酒精可能是醫學上的消毒劑，但決不可用來消毒飲用水。乙醇的濃度為50%至70%時比較有效，濃度低於20%時，殺菌能力基本上就不存在了。強度標為95的酒中含有47%的酒精。要提防甲基化酒精，那是劇毒的，永遠不能摻入飲用水。
 
    如果沒有其他安全的飲用水，水管中流出的燙手的水可以留下來冷卻。這種水一般是安全的。那些計劃去偏遠地區旅行，或在飲用水不現成的國家居住的人，應該知道如何使水適於飲用的各種辦法。