Lesson 38 Water and the traveller 水和旅行者

First listen and then answer the following question.

听录音,然后回答以下问题。

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 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 15 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

New words and expressions 生词和短语

contamination (1.1) $/k$ an taems 1’ neɪʃən $/n$ . 污染 sanitation (I.1) ${/}_{1}$ sæn ${\mathrm{I}}^{\prime }$ ter $\int a\mathrm{n}/n$ . 卫生,卫生设备 sewage (1.1) /’sjuːɪdʒ/n. 污水 leakage (1.2) $/$ li:kɪdʒ $/n$ . 泄漏 intermittent (1.4) / , Intə'mitənt/ adj. 间歇的, 断断续续的 carbonated (1.8) / 'kaːbəneɪtɪd/ adj. 碳化的, 碳酸的 acidic (1.8) / ə'sɪdɪk/ adj. 酸的, 酸性的

alcohol (1.16) /’ælkəhɒl/ $n$ . 酒精

disinfectant (1.16) ${/}_{1}$ dIsIn’fektant $/n$ . 消毒剂

sterilize (1.16) $/$ sterɪlaɪz $/v$ . 消毒

ethanol (1.16) $/{e\theta } \equiv {nD}\mathrm{l}/n$ . 乙醇

bactericidal (I.17) /backˌtɪərɪˈsaɪdəl/adj. 杀菌的

negligible (1.17) / neglɪdʒɪbəl/ adj. 可以忽略的, 微不足道的

methylated (l.18) /'meθɪleɪtɪd/ adj. 加入甲醇的

Unit 5 Lesson 38

A woman is drawing water from a well.

Notes on the text 课文注释

1 keep to, 局限于。

2 Ice is only as safe as the water from which it is made. 冰块只是当制造冰块的水安全时才是安全的。

3 know about,知道……的情况,了解。

参考译文

水源的污染通常是由于接近水源的地方卫生条件太差而造成的:污水排入水源,污水渗入给水系统或工农业污水造成污染。既使管道供水系统在水源处是安全的,等水到达龙头时就不一定总是安全的了。断断续续的水管应该被视为是非常可疑的。

短途旅行到水质不保险的地区时,应避免饮用水龙头的水或未经处理任何其他来源的水。最好仅饮用开水,名牌瓶装或罐装水——装瓶厂通常遵循国际水处理的标准。碳酸饮料是酸性的,就更安全一些。确保瓶子是当着你的面开启的,瓶口清洁干燥。

烧开一直是水处理的一种好办法。有的酒店根据要求可提供开水,这些开水可用于饮用和刷牙。如果有相配的电压, 可以煮少量水的便携式热水装置是有用的。应谢绝任何不明来源的冷饮。

冰块只有当制造冰块的水安全时才是保险的,只有知道冰块安全时才能加入饮料。可以把饮料置于冰块之上来冷却, 而不是把冰块加进饮料之中。

酒精可能是医学上的消毒剂,但决不可用来消毒饮用水。乙醇的浓度为 50% 至 70% 时比较有效,浓度低于 20% 时, 杀菌能力基本上就不存在了。强度标为 95 的酒中含 47% 的酒精。要提防甲基化酒精, 那是剧毒的,永远不能掺入饮用水。

如果没有其他安全的饮用水,水管中流出的烫手的水可以留下来冷却。这种水一般是安全的。那些计划去偏远地区旅行、或在饮用水不现成的国家居住的人,应该知道如何使水适于饮用的各种办法。

Unit 5 Lesson 38

Comprehension 理解

Answer these questions:

What kind of piped water could be dangerous to the health?

2 Why does the author recommend that travellers on short trips should drink canned drinks of well-known brand names?

3 Why could ice in drinks be dangerous to the health?

4 Why wouldn't you be safe if you added 95 proof alcohol to contaminated water?

5 What kind of tap water is generally safe to drink in the absence of other sources?

Vocabulary 词汇

Refer to the text to see how the following words have been used, then write sentences of your own using these words: poor (1.1); contamination (1.2); regarded (1.4); areas (1.5); plants (1.7); in your presence (1.8); supply (1.10); on request (1.10); refuse (1.12); remote (1.21); various (1.22).

Summary 摘要

Refer to lines 1-5 (‘Contamination ... adding ice to them,’). In not more than 80 words write seven sentences giving advice to travellers about drinking water. Begin each sentence with the word 'always'. The first sentence has been done for you:

Always avoid intermittent tap-water supplies.

Composition 作文

A A foreigner is going to travel to some of the remote regions of your country. Write some notes giving him/her good advice under each of these headings: the people, accommodation, food, water.

B Refer to your notes and write four paragraphs of advice to a traveller in about 400 words.

Key structures 关键句型

A Compare these active and passive uses of should for giving direct and indirect advice:

You should regard intermittent tap-water supplies as particularly suspect.

Intermittent tap-water supplies should be regarded as particularly suspect. (1.4)

Turn these sentences into the passive in order to give indirect advice:

1 You should avoid drinking tap-water.

2 You should prefer well-known brand names of bottled drinks.

3 They should open all bottles in your presence.

4 You should request boiled water in hotels.

5 You should boil water before drinking it.

Unit 5 Lesson 38

B Compare these active and passive uses of shouldn't for giving direct and indirect advice:

You shouldn't regard intermittent tap-water supplies as safe.

Intermittent tap-water supplies shouldn't be regarded as safe.

Turn these sentences into the passive in order to give indirect advice.

1 You shouldn't drink tap-water.

2 You shouldn't accept bottles of water that haven't been opened in your presence.

3 You shouldn't put ice in drinks.

4 You shouldn't rely on alcohol to sterilize water.

5 You shouldn't add methylated alcohol to drinking water.

Special difficulties 难点

A Compare the -ing form in these four sentences:

Boiling is always a good way of treating water. (1.10) (boiling-noun)

Portable boiling elements that can boil small quantities of water ... (1.11) (boiling-compound noun: i.e. elements

used for boiling)

I was scalded with boiling water. (boiling-adjective: i.e. water which was boiling)

The water is boiling. (boiling-participle: part of the verb form)

Identify the -ing forms as nouns, adjectives or participles in these sentences:

1 Travellers should avoid drinking tap water. (II.5-6)

2 International standards of water treatment are usually followed at bottling plants. (1.7)

3 Methylated alcohol should never be added to drinking water. (ll.18-19)

4 Those planning a trip to remote areas should know about various methods ... (II.21-22)

5 Making water safe to drink is a matter of life or death.

6 We are planning a trip to the remote areas of the country.

B Compare the -ed form in these two sentences:

Piped water supply is safe at its source. (1.3) (piped-adjectival past participle)

The water has been piped across thousands of miles. (piped-past participle: part of the verb form)

Identify the -ed forms as adjectives or past participles in these sentences:

1 Some water supplies should be regarded as particularly suspect.

2 Bottled or canned drinks are usually safe. (II.6-7)

3 Carbonated drinks are acidic. (1.8)

4 Make sure that all bottles are opened in your presence. (II.8-9)

5 Drinks can be cooled by placing them on ice. (1.15)

6 Spirits labelled 95 proof contain only about 47 per cent alcohol. (ll.17-18)

Multiple choice questions 多项选择题

Choose the correct answers to the following questions.

Comprehension 理解

1 Piped water could be contaminated, especially if _____

(a) it is supplied from the sewage system

(b) it isn't safe by the time it reaches the tap Unit 5 Lesson 38

(c) doesn't flow continuously through the pipes

(d) it comes from farmland

2 Make sure that bottled drinks are opened in your presence, presumably _____

(a) to be assured that it was filled at a bottling plant

(b) to make sure that it isn't too acidic to drink

(c) to check that the rim of the bottle is clean and dry

(d) because water supplies are uncertain

3 You should avoid ice in drinks because _____.

(a) you don't know if it has been made with contaminated water

(b) you can be sure it hasn't been boiled first

(c) because it always comes from an unknown source

(d) it hasn’t been treated in your presence

4 You can't use alcoholic drinks to sterilize water because _____ .

(a) only ethanol is capable of doing this

(b) the alcoholic content is rarely sufficiently concentrated to do the job

(c) methylated alcohol is very poisonous

(d) it's not a very good disinfectant

Structure 句型

5 Piped water _____ safe at its source, _____ it isn't always safe. (1.3)

(a) must be ... and (b) may be ... but (c) should be ... though(d)will be ... even if

6 It _____ to drink tap water of uncertain quality. (1.5)

(a) isn't advisable (b) is advisable (c) isn’t required (d) is required

7 Drinks can be cooled _____ them on ice. (1.15)

(a) so as to place (b) in placing (c) if you place (d) to place

8 _____ rely on alcohol to sterilize water. (1.16)

(a) Not (b) Don't (c) Must not (d) Not to

Vocabulary 词汇

9 Make sure that all bottles are opened . (1.8)

(a) at once (b) now (c) at present (d) in front of you

10 _____ any cold drink from an unknown source. (1.12)

(a) Discard (b) Prevent (c) Deny (d) Don't accept

11 You should not _____ on alcohol to sterilize water. (1.16)

(a) depend (b) insist (c) lean (d) support

12 Those planning a trip to _____ places ... (1.21)

(a) away (b) far away (c) contaminated (d) overseas