# 第四册 Lesson 38 Water and the traveller 水和旅行者

## 一、课文原文

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 keep 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. Drinks can be cooled by placing them on ice rather 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 water 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*

## 二、重点词汇详解

| 单词 | 音标 | 词性 | 释义 | 用法说明 |
|------|------|------|------|----------|
| contamination | /kənˌtæmɪˈneɪʃn/ | n. | 污染 | contaminate v. 污染 |
| sanitation | /ˌsænɪˈteɪʃn/ | n. | 卫生设施 | poor sanitation 卫生条件差 |
| sewage | /ˈsuːɪdʒ/ | n. | 污水 | sewage disposal 污水处理 |
| leakage | /ˈliːkɪdʒ/ | n. | 泄漏 | leakage of sewage 污水泄漏 |
| intermittent | /ˌɪntəˈmɪtənt/ | adj. | 间歇的 | intermittent supply 间歇供应 |
| suspect | /səˈspekt/ | adj. | 可疑的 | particularly suspect 尤其可疑 |
| carbonated | /ˈkɑːbəneɪtɪd/ | adj. | 碳酸的 | carbonated drinks 碳酸饮料 |
| rim | /rɪm/ | n. | 边缘，瓶口 | bottle rim 瓶口 |
| disinfectant | /ˌdɪsɪnˈfektənt/ | n. | 消毒剂 | medical disinfectant 医用消毒剂 |
| sterilize | /ˈsterəlaɪz/ | v. | 消毒，灭菌 | sterilize water 给水消毒 |
| ethanol | /ˈeθənɒl/ | n. | 乙醇，酒精 | ethanol concentration 乙醇浓度 |
| bactericidal | /bækˌtɪərɪˈsaɪdl/ | adj. | 杀菌的 | bactericidal action 杀菌作用 |
| negligible | /ˈneɡlɪdʒəbl/ | adj. | 可忽略的 | negligible effect 微不足道的效果 |
| methylated | /ˈmeθɪleɪtɪd/ | adj. | 甲基化的 | methylated alcohol 甲醇/变性酒精 |

**固定搭配：**
- **due to**：由于
- **keep to**：坚持，只使用
- **on request**：应要求
- **beware of**：当心

## 三、语法知识点

### 1. even if 让步状语从句

> **Even if** a piped water supply is safe at its source, it is not always safe by the time it reaches the tap

even if = 即使，引导让步状语从句。

### 2. by the time 时间状语从句

> by the time **it reaches** the tap

by the time + 过去时/现在时，表示"到……时候"。

### 3. only as...as 同级比较

> Ice is **only as safe as** the water from which it is made

as...as 同级比较，only 限制范围。

### 4. rather than 表示选择

> by placing them on ice **rather than** adding ice to them

rather than 而不是，连接两个并列的动名词。

## 四、重点句型分析

### 句型1：多重原因列举

> Contamination of water supplies is usually due to **poor sanitation...**, **sewage disposal...**, **leakage of sewage...** or **contamination with industrial or farm waste**

四个原因并列，结构清晰

### 句型2：实用建议句式

> Travellers...**should avoid** drinking tap-water
> It is best to **keep to** hot drinks
> **Make sure that** all bottles are opened in your presence
> **Refuse politely** any cold drink from an unknown source

- 情态动词 should + 动词原形
- It is best to + 动词原形
- 祈使句 Make sure / Refuse

### 句型3：条件假设

> **If** no other safe water supply can be obtained, tap water that is too hot to touch can be left to cool

- if 条件从句
- too...to... 太……以至于不能

## 五、课文翻译

供水污染通常是由于水源附近卫生条件差、污水直接排入水源、污水泄漏到供水系统或工业和农场废物污染所致。即使管道供水在源头是安全的，到达水龙头时也不一定安全。间歇性自来水供应应被视为特别可疑。

短期前往水质不确定地区的旅行者应避免饮用自来水或任何其他来源的未经处理的水。最好只喝热饮、知名品牌的瓶装或罐装饮料——装瓶厂通常遵循国际水处理标准。碳酸饮料呈酸性，稍微安全一些。确保所有瓶子在你面前打开，并且瓶口干净干燥。

煮沸始终是处理水的好方法。有些旅馆应要求提供开水，可用于饮用或刷牙。当电压合适时，可以煮沸少量水的便携式加热器很有用。礼貌地拒绝任何来自不明来源的冷饮。

冰只和制作它的水一样安全，除非确认安全，否则不应放入饮料中。饮料可以通过放在冰上冷却，而不是把冰加入饮料中。

酒精可能是医用消毒剂，但不应该依赖它来给水消毒。乙醇在50-70%的浓度下更有效；低于20%时，其杀菌作用微乎其微。标有95 proof 的烈酒仅含约47%的酒精。当心甲醇，它非常有毒，绝不应该加入饮用水中。

如果没有其他安全水源，太烫手而无法触摸的自来水可以放凉后饮用，通常是安全的。计划前往偏远地区旅行，或打算居住在饮用水不现成的国家的人，应该了解各种使水安全可饮的方法。

## 六、语言点精讲

### 1. 写作手法：实用说明文

- 文章为旅行健康指南，采用清晰的段落结构
- 每段一个主题：污染原因→饮水建议→煮沸法→冰→酒精→应急措施

### 2. 逻辑结构

| 段落 | 主题 | 内容 |
|------|------|------|
| 第一段 | 水污染原因 | 四种污染途径 |
| 第二段 | 短期旅行建议 | 避免自来水，选择安全饮料 |
| 第三段 | 煮沸法 | 最可靠的水处理方式 |
| 第四段 | 冰的注意事项 | 冰与水源同质 |
| 第五段 | 酒精的误区 | 不能依赖酒精消毒 |
| 第六段 | 应急措施与总结 | 热水冷却法 |

### 3. 文化背景

- "proof"：酒精度数表示法，95 proof ≈ 47.5% ABV
- 甲基化酒精（methylated alcohol）：添加了甲醇的变性酒精，有毒
- 旅行医学（Travel Medicine）是20世纪后期兴起的学科

### 4. 修辞分析

- 语气客观实用，避免夸张
- 祈使句增强指导性（Make sure、Refuse、Beware）
- "Ice is only as safe as the water from which it is made"——简洁有力

## 七、课后练习要点

1. **词汇练习**：掌握 contamination、sanitation、sewage、sterilize、bactericidal 等核心词
2. **语法练习**：even if 让步从句；rather than 选择结构；only as...as 比较句
3. **翻译练习**：注意实用说明文的准确翻译
4. **写作练习**：模仿课文的实用说明文风格，写一篇旅行安全指南

## 八、本课小结

本课为旅行者提供饮用水安全指南。核心内容：**水源可能被污染，旅行者应避免饮用自来水和加冰饮料，煮沸是最可靠的水处理方法，酒精不能用来消毒水**。文章结构清晰，每段一个主题，语言简洁实用。语法重点为 even if 让步从句和 rather than 选择结构。