托福阅读长难句精讲：when引导的时间状语从句

## 托福阅读长难句 However, research has shown that children often have difficulty understanding disclaimers: children may interpret the phrase ‘when part of a nutritionally balanced breakfast’ to mean that the cereal is required as a necessary part of a balanced breakfast. ## 专家解析 ### 【子句拆分】 主句：However, research has shown something. 宾语从句1：Children often have difficulty understanding disclaimers. 同位语从句：Children may interpret the phrase ‘when part of a nutritionally balanced breakfast’ to mean something. 宾语从句2：The cereal is required as a necessary part of a balanced breakfast. ### 【成分划分】 主句：However, [状语] research [主语] has shown [谓语] something [宾语] . 翻译：但是，研究表明某事。 连接词：that 宾语从句1：Children [主语] often [状语] have [谓语] difficulty [宾语] understanding disclaimers [定语] . 翻译：儿童常常对理解免责声明有困难。 同位语从句：Children [主语] may interpret [谓语] the phrase [宾语] ‘when part of a nutritionally balanced breakfast’ [同位语] to mean something [宾语补足语] . 翻译：儿童可能会把“当其作为营养均衡早餐的一部分时”这一措词理解成为某事。 连接词：that 宾语从句2：The cereal [主语] is required [谓语] as a necessary part [主语补足语] of a balanced breakfast[定语] . 翻译：谷类食品是营养均衡早餐所必需的组成部分。 ### 【全句翻译】 但是，研究表明，儿童常常对理解免责声明有困难：儿童可能会把“当其作为营养均衡早餐的一部分时”这一措词理解成为“谷类食品是营养均衡早餐所必需的组成部分”。 ## 知识点梳理 ### when引导的时间状语从句 一般来讲，when 的意思相当于 at that time ，因此从句的谓语动词通常是短暂动词，表示某一时刻的动作。不过，when 引导的从句也可以接延续性动词，这时从句往往用过去进行时态，表示某一时间段内发生的动作。 时间状语从句所表述的时间概念不外乎三种：过去、现在和将来。我们先来看看 when引导的时间状语从句表示过去动作的五组时态搭配。 1. 主句一般过去时 + 从句一般过去时 例句： I stared my dinner when he left. 2. 主语一般过去时 + 从句过去完成时 例句： He left when I had got there. 3. 主句过去完成时 + 从句一般过去时 例句： He had already left when I got there. 4. 主句一般过去时 + 从句过去进行时 例句： The doorbell rang when I was telephoning. 5. 主句过去进行时 + 从句一般过去时 例句： I was telephoning when the doorbell rang. 下面，我们来看 when引导的时间状语从句表示将来动作的四组搭配。 1. 主句一般将来时 + 从句一般现在时 例句： I'll speak to him when he arrives. 2. 主句一般将来时 + 从句现在完成时 例句： I'll give you a call when I have finished the work. 3. 主句将来完成时 + 从句一般现在时 例句： The performer will already have played the music when we get there. 4. 主句将来进行时 + 从句一般现在时 例句： The performer will be playing the music when we get there. 最后，我们来看一下 when引导的时间状语从句表示一般现在动作的搭配。 1. 主从句都用一般现在时 例句： Live your life so that when you die, the world cries and you rejoice.