西瓜英语

Hot snake

原文

At last firemen have put out a big forest fire in California. Since then, they have been trying to find out how the fire began. Forest fires are often caused by broken glass or by cigarette ends which people carelessly throw away.

Yesterday the firemen examined the ground carefully, but were not able to find any broken glass. They were also quite sure that a cigarette end did not start the fire.

This morning, however, a firemen accidentally discovered the cause. He noticed the remains of a snake which was wound round the electric wires of a 16,000-volt power line. In this way, he was able to solve the mystery.

The explanation was simple but very unusual. A bird had snatched up the snake from the ground and then dropped it on to the wires. The snake then wound itself round the wires. When it did so, it sent sparks down to the ground and these immediately started a fire.

译文

At last firemen have put out a big forest fire in California. Since then, they have been trying to find out how the fire began. Forest fires are often caused by broken glass or by cigarette ends which people carelessly throw away.

Yesterday the firemen examined the ground carefully, but were not able to find any broken glass. They were also quite sure that a cigarette end did not start the fire.

This morning, however, a fireman accidentally discovered the cause. He noticed the remains of a snake which was wound round the electric wires of a 16,000-volt power line. In this way, he was able to solve the mystery.

The explanation was simple but very unusual. A bird had snatched up the snake from the ground and then dropped it on to the wires. The snake then wound itself round the wires. When it did so, it sent sparks down to the ground and these immediately started a fire.

词汇表

put out

动词短语
定义
1. 扑灭 - To extinguish or stop something, such as a fire.

例子: The firefighters put out the forest fire before it spread further.

例子: We need to put out the candles before leaving the room.

2. 发布 - To make something public or available.

例子: The company put out a statement about the incident.

例子: She put out a new book last year.

近义短语
extinguish: 更正式且直接，常用于专业语境，如消防领域，而 'put out' 更通用且口语化。
quench: 常用于液体或火，通常更诗意或文学化，强调彻底消除，而 'put out' 更实用。
douse: 强调用液体扑灭火，常用于紧急情况，相比 'put out' 更具体到方法。
反义短语:
start a fire, ignite, set alight
用法
常用于描述灭火或发布信息，适用于正式和非正式语境，如 'put out a fire'（扑灭火灾），但在新闻或故事中常见。文化背景中，常与紧急响应相关。
变体:
puts out, putting out

关键句型 "Since then, [subject] have been [verb-ing]."

定义

此句型用于描述从过去某个时间点开始一直持续到现在的一种动作或状态，强调动作的持续性。结构为：Since then（从那时起）+ [subject]（主语）+ have been（现在完成进行时的助动词形式）+ [verb-ing]（动词的现在分词形式）。根据《剑桥英语语法》教材，这种句型是现在完成进行时的典型表达，常用于表示从过去到现在的一段时间内发生的活动。

例如，在文章中，“Since then, they have been trying to find out how the fire began.” 清楚地展示了从“那时起”消防员一直在调查火因。

它帮助学习者表达时间延续的动态过程，非常适合描述持续的行动或变化。

用法

此句型主要用于叙述从过去某个具体事件开始一直延续到现在的动作，常出现在叙述故事、报告事件或日常对话中。规则：Since then 通常置于句首，表示时间起点；have been 用于第一人称、第二人称或第三人称复数；[verb-ing] 表示进行中的动作。

在语法体系中，它属于现在完成进行时的一部分，与一般现在时或现在完成时形成对比。横向比较：与 "They have tried to find out"（现在完成时）相比，此句型强调动作的持续过程，而非结果；与 "They are trying to find out"（一般现在进行时）相比，它突出从过去开始的延续性，更适合长时段描述。与过去完成进行时（如 "They had been trying"）的联系在于，都强调持续，但前者连接过去和现在，后者仅限于过去。

跨语法点联系：学生可将此句型与时间状语（如 "for two hours"）结合使用，进一步扩展到其他时态，如 "I have been studying for three hours."

注意事项

学生常犯的错误包括：误用 have been 为 has been（如在第三人称单数时混淆，例如 "He have been working" 应为 "He has been working"）；或忽略 since then 的具体时间含义，导致句子模糊。纠正建议：始终确保主语与助动词的数和人称一致，并使用具体时间词来强化延续性。

另一个常见偏误是与简单过去时混淆，如说 "They tried since then"，这忽略了持续性。提供例句：

错误示例：Since then, they tried to find out the cause.  （这暗示动作已完成，没有延续性）
正确示例：Since then, they have been trying to find out the cause.  （强调从那时起一直持续到现在）

练习时，注意语调的平稳，以突出持续感。

练习

原创例子：假设你在描述个人经历，可以说：“Since then, I have been learning English every day to improve my skills.” 学生可以替换 [subject] 为 "We" 或 "My friends"，并改变 [verb-ing] 为 "working" 或 "traveling"，如在旅游场景中说：“Since then, we have been exploring new cities around the world.”

这种替换练习能帮助学生将句型应用到日常生活，例如在工作报告中描述项目进展，增强实际表达能力。

额外内容

背景知识：这种句型源于英语中对时间延续的强调，英语作为一种分析语言，常通过助动词和分词来表示动态过程。在文化背景上，英语叙述往往注重时间线，这在新闻报道中很常见，如文章的描述。对比分析：与中文的 "从那时起，他们一直在..." 类似，但英语更依赖语法结构（如助动词）而非词汇；与法语的类似表达（如 "depuis lors, ils ont été en train de..."）相比，英语的结构更简洁，便于初学者掌握。

学习此句型还能为更复杂的叙述铺路，如结合条件句 "If I had started earlier, I would have been working on it since then."，帮助学生构建更丰富的故事。

关键句型 "When [subject] did so, [subject] [verb]."

定义

此句型用于描述一个动作发生后立即引发的另一个动作，常通过时间状语从句表达因果或顺序关系。结构为：When（当…时）+ [subject]（主语）+ did so（如此做）+ , + [subject] + [verb]（主要动作）。根据《牛津现代英语语法》，did so 是指代前面提到的动作的简洁方式，用于避免重复，提升句子流畅性。

文章中的例子是：“When it did so, it sent sparks down to the ground.” 这里，“it did so” 指代蛇缠绕电线的动作。

此句型在叙述事件时特别有用，帮助连接前后事件，形成连贯的故事。

用法

此句型常用于故事讲述、说明书或报告中，表示时间顺序或结果。规则：When 引导时间从句，did so 必须指代前文提到的具体动作；主句描述后续结果。Did so 可以替换较长的短语，使语言更简洁。

在语法体系中，它涉及时间状语从句和代词用法，与其他从句类型（如条件从句）相关。横向比较：与 "After it did that, it sent sparks" 相比，此句型更精确地表示同时性；与 "If it did so"（条件从句）相比，它强调实际发生而非假设。与简单句的联系在于，它可以扩展为复杂句，增强描述的深度。

跨语法点联系：学生可将其与过去时或过去完成时结合，如 "When he arrived, he had already called."，从而学习句间关系。

注意事项

学生易犯的错误是误用 did so，如不指代正确动作（例如，用在没有前文支持的句子中），导致句子含糊。纠正建议：确保 did so 总是回指前一句的关键动作，并保持时态一致。

另一个问题是忽略逗号分隔从句，如写成 "When it did so it sent sparks"，这会影响可读性。提供例句：

错误示例：When the snake wound around, it sent sparks without doing so.  （逻辑混乱，did so 未正确指代）
正确示例：When the snake wound around, it did so and sent sparks down.  （清晰指代动作）

练习中，强调上下文的重要性，以避免指代不清。

练习

原创例子：在日常对话中，你可以说：“When I finished my homework, I did so and went out to play.” 学生可以替换 [subject] 为 "She" 或 "The team"，并修改 [verb] 为 "called back" 或 "started the engine"，如：“When the driver signaled, he did so and turned the corner safely.”

通过这种替换，学生能应用于实际场景，如描述事故报告或个人经历，强化句型的灵活性。

额外内容

背景知识：Did so 的用法体现了英语的简洁性，源自18世纪的语法演变，旨在减少冗余。在文化上，英语故事叙述常使用这种结构来保持节奏感。对比分析：与西班牙语的类似表达（如 "cuando lo hizo"）相比，英语更依赖代词；与中文的 "当它那样做时，它..." 类似，但英语通过 did so 使句子更紧凑。

掌握此句型后，学生可扩展到更高级的写作，如新闻报道，增强语言的连贯性。