同学你好，该知识点来自沪江网校《新概念英语2、3、4册连读【双11专享班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好～

课文原文：
However, he had at last been allowed to send a fax in which he informed the editor that he had been arrested while counting the 1,084 steps leading to the fifteen-foot wall which surrounded the president's palace.
不过，他终于获准发回了一份传真。在传真中他告诉编辑，就在他数通向15英尺高的总统府围墙的1，084级台阶时，被抓了起来。

语句解析：
1. he had at last been allowed = he had at last been permitted = he had asked for permission
请求允许，被允许：be allowed to do = be permitted to do = ask for permission to do sth.

2. In which是“prep.+关系代词”结构，引导定语从句，修饰fax。
That引导宾语从句，说明informed的内容。

3. while和现在分词（-ing)搭配，做时间状语，表示“正在做某事的过程中”
可用用while引导的时间状语从句去替换
while counting = while he was counting

4. Leading to …为现在分词短语，作定语，修饰steps。
the steps leading to the president's palace
类似用法：the road leading to the forest

5. fifteen-foot……做前置定语，这里的名词必须上单数形式

6. 第二个which引导定语从句，修饰wall。

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