关于when和if的区别

ricee

今天看到大全的一道题，想到另外两题：

OG11-8. Rising inventories, when unaccompanied correspondingly by increases in sales, can lead to production cutbacks that would hamper economic growth.

(A) when unaccompanied correspondingly by increases in sales, can lead

(B) when not accompanied by corresponding increases in sales, possibly leads

(C) when they were unaccompanied by corresponding sales increases, can lead

(D) if not accompanied by correspondingly increased sales, possibly leads  (E)

(E) if not accompanied by corresponding increases in sales, can lead

OG ：When indicates a period of time; if indicates a condition. If is preferable here. Can lead indicates a possibility that continues 

OG11-126.A wildlife expert predicts that the reintroduction of the caribou into northern Minnesota would fail if the density of the timber wolf population in that region is more numerous than one wolf for every 39 square miles.

(A) would fail if the density of the timber wolf population in that region is more numerous than

(B) would fail provided the density of the timber wolf population in that region is more than

(C) should fail if the timber wolf density in that region was greater than

(D) will fail if the density of the timber wolf population in that region is greater than (D)

(E) will fail if the timber wolf density in that region were more numerous than

OG：The prediction is made using the construction y will happen ix happens first (an alternate form is if x happens, y will happen). Here, the if clause uses the present tense: x (the density of the wolf population) is. The main clause must use the future tense, y (the reintroduction of caribou) will fail, not the conditional would fail.

OG：The prediction is made using the construction y will happen ix happens first (an alternate form is if x happens, y will happen). Here, the if clause uses the present tense: x (the density of the wolf population) is. The main clause must use the future tense, y (the reintroduction of caribou) will fail, not the conditional would fail.

 

       大全sec12-19 Although it claims to delve into political issues, television can be superficial such as when each of the three major networks broadcast exactly the same statement from a political candidate.

(A) superficial such as when each of the three major networks

(B) superficial, as can sometimes occur if all of the three major networks

(C) superficial if the three major networks all

(D) superficial whenever each of the three major networks（E）

(E) superficial, as when the three major networks each

 

我的问题是，从上面三道题可以看出when和if大概有这样几种搭配：

- If A happens, B can happen

- If A happens, B will happen

- When A happens, B can happen

那么当结果部分都是can happen这样的表可能性的陈述时，if 和when怎么区分呢？

当条件部分都是if A happens，结果部分will和can有没有什么区别呢？

 

希望能有人一起讨论一下，谢谢先

[此贴子已经被作者于2008-3-9 11:50:42编辑过]

ricee

光速自问自答1：

刚查了longman,关于can的解释忽然有新发现：can的解释

1.possibility - used to say that something is possible

2.sometimes - used to say what sometimes happens or how someone sometimes behaves

所以，结果从句部分，题OG11-8与大全sec12-19的意思是不同的，前者表possibility，后者表sometimes；故前者的条件从句用if，而后者用的是表时间概念的when。另外，as when的解释也应该是(such) as when比较确切吧。

而if条件从句后面的结果部分，个人感觉will比can更加肯定.

open 4 discussion

pissunrise

我觉得很难去判断后者是否是表时间概念还是前提条件的概念，这2个概念使用应该可以由作者根据其所判断的情况去自由表达的，导致我们在单句改错中很难判断if与when的区别。


因此我觉得不需要用when/if区别来作为判断，至少在这3题里面都是不需要用这个split的。OG13的解释中把第一题的解释去掉了关于when与if的区分，我想也是部分由于这个原因，毕竟2种说法都能站得住脚。


第1题的判断，OG13是建立在unaccompanied，correspondingly by increases in sales， leads 这3点上，没有涉及when与if的区分。另外值得提出的是主句划线后 cutbacks that would hamper economic growth里面有would的使用，但我想这并不能证明什么，因为这只是cutbacks的限制性定语从句，与主句的内容无关。


第2题的判断，OG是建立在虚拟条件句的时态搭配上，并且没有when的选项，无法判断if&when的区别。


第3题的判断，我想是在C的the three major networks以及E的as when的判断上。C中if引导的条件状语从句中，the一般表示特指；而主句的名词television是表示泛指概念，主句用泛指，而其条件从句反而用特指，这种用法应该是有问题的；
而E，首先说as when引导的状语起举例的作用，其正确性已经被很多NN用多种方法确认，其中我认为最容易理解的一个是 as (it is) when, 因为多余而省略it is；因此整句是 “尽管它..., television也可能是superficial，比如这种情况：3个networks都播放同个内容”
因此 the 3 major networks 所起到的也只是举例作用，特指可以理解成被省略在内，或者是特指在该国众所周知的3家major networks，或者也有可能由于其它我所不了解的原因，但是至少比C的情况更优，没有用特殊的情况推出普遍的情况，并且作为举例，整个句意更为通顺。


PS：在最后一题的判断上，大家可以看另外2贴讨论，对于这2种说法，我还是不能完全理解，因此也就无法赞同，哪位NN可以解释一下。


http://forum.chasedream.com/GMAT_SC/thread-15663-2-1.html

从逻辑意思上并非假设关系。
C中
superficial if the three major networks all
意思是“如果。。。，则可能肤浅”
言外之意是“如果不同时播同一个东西就不肤浅”
显然不如E好。
-- by 会员 gemj (2003/10/31 23:53:00)

http://forum.chasedream.com/archiver/GMAT_SC/thread-576453-1.html
First of all, there's the "if..." construction. if taken literally (as you MUST do), the sentence implies only that television can be "superficial" IN THE SPECIFIC EVENT THAT all 3 major networks broadcast the same political statement.


第一条引用所说，播放-->肤浅，言外之意是 不播放-->不肤浅。if所引导的条件是必要条件，否则不能得出这个言外之意。


第2条television can be "superficial" in that all 3 major ...   即superficial的原因被限定在that范围内，只有all 3 major... 才会superficial，if引导的应是一种充分条件并且还附带排除其他所有可能性。


这两种用法我都查不到来源，不知道这2个表达哪种对。


但是假如我坚持 只有3 major broadcast exactly the same的时候，television才会是superficial，从本句所提供的信息来看，并不能判定我这种逻辑是错的。因为大家都不知道实际情况，只能从错误的原句中得的片面的信息，而且我们所能得到的仅有的信息碎片其本身就有可能是错误的，那么我们又怎么能从一两个词的使用来推断原句的逻辑，我们所做的只是把原句表达不清的部分重新整理让其逻辑清晰一致而已，当潜在的可能的逻辑存在好几个的时候，就不能随便判断其他情况的是错的，或者是不好的。


并且为什么when不会表示同样的意思？因为when在这时候也是表达一种特定情况，或者说一种条件。


求指点，有砖轻拍别打脸

huanglianjing

if 条件状语从句，而WHEN只能引导时间状语从句！！！！！语法笔记中出现过when的说明，切记不可引导条件状语从句

pissunrise

我的意思不是说when在引导条件状语从句，只是说when在这时候表达的意思，意思啊... 当...时，有一种类似于条件的意味，但绝不是说事件发生的必要条件.      

一定要揪这个的话，参 https://e-gmat.com/blogs/?p=169
‘If’ and ‘when’ can be used interchangeably when we present conditions in which the outcome is definite or the outcome is a general fact. i.e. if event A happens, event B happens.

When ‘if’ conditional statement is used to express a situation in which the outcome is a possibility and not a certainty, ‘when’ cannot be used in place of ‘if’.
反观1L提出的3题，前2题可以用这个解释，但是第3题还是有点牵强。
因此第3题选E好在 1，没有用特指推出泛指；2，用as when举例让整句更加通顺易理解，正如gemjNN在第一句提出的 从逻辑意思上并非假设关系

coconutmi

pissunrise 发表于 2013-3-6 14:20
我觉得很难去判断后者是否是表时间概念还是前提条件的概念，这2个概念使用应该可以由作者根据其所判断的情 ...

大侠还在吗?我想请教一下, og13-14中E选项中if条件句是不是省略了be动词，条件句可以这样省略吗？  多谢！