mark：AB两项由于主语与前面状语的主语不一致，时态不能是过去完成时，被排除；同时suggest后面只能接宾语从句；(1) ... emerged earlier than previously thought. (2) ... emerged earlier than that which was previously thought.(3) ... emerged earlier than that previously thought.
All three of those are 100% grammatically correct. Saying anything with more words than needed is always wrong on the GMAT SC.
Both (D) and (E) use the noun "emergence" over the verb "emerge"。

AC

A对C不对，是因为along with 引导的内容在重要程度上不如前面主句说的内容吗？

我觉得这道题最关键的是认清“直接原因”。 选项A和选项B虽然都是对比，但是租金，用品成本的改变，总贷款的变化，都不是能导致还贷款变化的直接原因。直接原因：百分之百导致结果发生的原因。一条逻辑链里离结果最近的那个因素才是直接原因。

mark一下：类似于这种某人通过一个“媒介”来做某事的，都被认为是“媒介”发出的动作，即，以最终发出动作的名词为标准；平行结构：后面有for changes 前面应该是argue for 而不是advocate；A选项，arguing in a treatise for women不能做主句的伴随状语，因为，发出argue这个动作的只能是Discourse on Women，而a treaties与Discourse语意重复

Mark: Ron给的例子感觉也可以解释，信被写的时间和数量超过没有关系。
my brother, who ate bagel bites for breakfast every single day of his high school career, graduated in 1994. --> correct; his eating bagel bites had no impact on his graduation date.
my brother ate bagel bites for breakfast every single day of his high school career, graduating in 1994. --> incorrect; these are two unrelated observations, but this construction erroneously implies some sort of relationship.

为什么是类比推理呢？ 并没有两个相似的可以类比的主题啊？

E选项that are和C选项there be句型都是不优的，A选项now和currently语意重复

"in which" --- the location
whereby indicates that the library is ameans of gathering and systematizing, instead of a place where this happens.
by which indicates that the library is an agent of gathering and systematizing, which makes no sense.

错选C 题干里有一句话 “哪怕在适合建风电水电工厂的地方也建蒸汽工厂” 本能地对这句话进行解释 猜想资本家考虑到未来大概率都要转型蒸汽工厂 索性直接建设蒸汽工厂 节省昂贵的“改建费用” E选项个人认为无法对上述题干情况进行解释 虽然风能水能工厂总数量无法满足需求 不代表同一个地点性价比低于蒸汽工厂 适合建风能水能工厂的地方没必要建蒸汽工厂（不足的能源可以多建蒸汽工厂在地理位置差的地方）
以上解释我选错原因 但是这道题的问题部分只讲到了“proliferation of steam-powered factories” 不确定是否涵盖“建造在适合建风能水能工厂的地方” 如果只考虑蒸汽工厂大量建造 那么E选项是合理的 个人不太喜欢这题

只有WHETHER可以表示是否，IF不可以, GMAC认为在宾语从句中用if有歧义

so …as...通常用于否定句中，在肯定句中应该写为as…as…

Mark：choice (d) uses "this" as a standalone pronoun. that's pretty much never acceptable in a formal written sentence.
if you're going to use "this", you should use it as an adjective: this thing, this finding, this statistic, etc.

C: COMMA + -ING modifiers must modify the preceding clause, but the -ING participle must also apply to the subject of the preceding clause.
therefore, the use of that comma+ing modifier would imply that the islets themselves are stimulating disputes. that's not true.

they, their, it都是完整指代，即指代包含了被指对象的所有修饰成分， that， one都是核心指代。
搬运自曼哈顿论坛：D的错误，首先，如果这个时间段已经结束，那么就不能用现在完成时； B中，你不能在这个结构中 使用that,因为that of(或者that+其他介词)必须有完全平行的结构，如果后一半说的是that during 10000 years,那么前一半必须是the growth of... during...(或其他介词，如before or after来代替during);此外from when是没有问题的，因为从句以from when开头是一个很完美的名词性从句；但是呢，the beginning of agriculture毫无疑问比when agriculture begin好（因为一个actual noun总是比一个名词从句更好一些）

Mark：C选项：COMMA + -ING is always an adverbial modifier; it always modifiers the preceding CLAUSE

a选项的its没有指代的歧义吗？

请问如何提高语法和逻辑 在短时间内

我想尝试一对一课程，只针对VERBAL 。想咨询下怎么上，我在加拿大

qualify在这里是限定的意思。第二段是18世纪末19世纪初，银行信用扩张对经济的正面作用，最后一句是反例，是指出上述论调的局限性

Some critics blame this impasse on environmentalists, (whom they believe fail to address the economic issues of environmental degradation.) fail to 后面的一串就是C所谓的 a particular strategy