以下是引用helenyu529在2007-1-31 23:18:00的发言:看了楼上们的发言,我感觉大家其实还是应该把OG的解释看仔细先,OG解释本身就能解决好几位XDJM的问题。
In which or when can be used interchangeably in this sentence. 前者引导的是定语从句,后者引导的是引导时间状语从句。(这个理解对吗?)
这个不对!, 根据薄冰语法书: 引导定语从句的关联词有关系代词和关系副词. 关系代词在定语从句中可用作主语,宾语,定语等.
关系副词在定语从句中只用作状语. 请看清楚是关系副词这个词(如When, Where, Why)等在定语从句中作状语, 并不是整个句子作状语从句. 当然在别的地方这些词是可以引导状语从句的,这点我并不否认.
eg: He came last night when I was out
I shall never forget the day when we first met in the park.
它们引导的都是定语从句.
The verb form here should be the simple past
existed rather than the past perfect had existed. 时态上之所以用一般现在时,我认为有两个原因:1. “the concept of an age in which/when...”所叙述的是一个“真理”或者“事实”,应该用一般现在时/一般过去时,而现在时和过去时由age决定。根据句义,这个age应该是发生在过去,所以用一般过去时;2. 主句谓语动词为动词短语lead sb. to do sth.——led L.A. to propose the concept of an age...,而the concept of an age是propose的宾语,所以和主句谓语动词lead的时态无直接联系;3. 定语从句只有一个谓语动词exist,并没有出现另外一个发生在exist之后的过去的动作,所以exist不需要使用过去完成时。
Now currently is redundant because both adverbs express the same idea.
A Had existed should be existed; now currently is redundant
B Correct. The simple past verb tense is correctly used in this sentence; now is placed and used correctly.
C Where there were areas now temperate is wordy and confusing
D
Had existed should be existed; current should be currently; in current temperate areas is unclear[current temperate areas的说法不正确。这种说法只有在current 和temperate都修饰areas的时候才正确;但是,current areas显然不合理。正确的说法是currently temperate areas,用副词currently 修饰temperate,意思为“现在气候温和的地区”]
E Now is an adverb and should be placed just after the verb are. [正确说法为:when great ice sheets existed in areas that are now temperate]
希望大家踊跃指正!