well, d has two problems, at least:
- 'projects X to do Y' is unidiomatic. (you can just say 'projects NOUN', as is done in choice e, or you can say something like 'projects that X will do Y').
- an average is a single data point, so there's no such thing as 'averag[ing] from 1.8 to 6.3'. on the other hand, it's quite possible for a single data point to fall between two given values.

i've seen 'of between' in this sense before - think of the phrase 'between 1.8 and 6.3' as standing for a single number, and parse the sentence accordingly (it reads as if it said 'average g.w. of 5 degrees', for instance) - so, if the original poster has copied the problem correctly, we now know that the gmat accepts that construction.

Prep2007E1-SC-154

In general,

1 * if you have than/as + subject + FORM OF "TO BE" as the second half of a comparison, then you must have another form of "to be" in the first half of the comparison.
or, there should be something in the first half that would make sense with "to be" in front of it.

2 * if you have than/as + subject + HELPING VERB as the second half of a comparison, you can have just about any other form of the same verb in the first part, as determined by context.

3 * if you have than/as + subject + FORM OF "TO DO" as the second half of a comparison, then you must have an ACTION VERB[/b] (or another form of "to do") in the first half of the comparison.

here are some examples:
#1
the air quality of las vegas is higher this year than it was in 2005.
parking spots are disappearing much more quickly today than they were yesterday.
#2
james can negotiate with salespeople more effectively than stephanie can. (comparing their abilities)
james can negotiate with salespeople more effectively than he does. (his ability exceeds his actual performance, probably because he just isn't trying very hard)
#3
parking spots disappeared much faster today than they did yesterday.
tanya eats more slowly than she did when she was a teenager. (note that "did" doesn't have to have the same tense as the action verb)

B) you can't use 'that' in this sort of construction, because constructions using 'that of' (or other preposition after 'that') must have EXACTLY parallel structures. in other words, if the second half says 'that during 10,000 years', then the preceding half must say 'the growth of ___ during something else' (or some other time preposition, such as before or after, in place of during).

there's nothing ungrammatical about 'from when', because the clause starting with 'when' is a perfectly legitimate noun clause (i.e., 'when agriculture began' serves as a noun. however:
- regardless of where the gmat stands on the issue, 'the beginning of agriculture' is unquestionably better than 'when agriculture began' (i.e., an actual noun is almost always superior to a circuitous noun clause, when possible)

C) first, you've got a "which" modifier that isn't preceded by a comma, so that's an automatic failure. (note that you can use preposition + which without a comma -- e.g., the box in which you placed your valuables -- but you cannot do so with just plain "which".)
more importantly, "had been" is not parallel to anything in the other half of the sentence; in order to use a parallel structure that contains a form of "to be", you must have another form of "to be" in the other half of the parallel structure.

D) you can't use the present perfect if the time interval is over. If the trend continues into the present day, then the present perfect is appropriate.
Even if that were fixed, choice D still suffers from fatal wordiness / lack of concision, especially in comparison to the correct choice."

E) 'what it did' doesn't make any sense:
* the growth didn't 'do' anything
* there's no other verb to which 'did' could logically be parallel to complete the comparison

比较前后状态一致

把主谓抽出来jay can remember and tends to

the fused clavicles (the "wishbone") of birds differ from the unfused clavicles of theropods.-->鸟类的锁骨是fused而theropod的是unfused（这是两种不同样的骨头），所以认为鸟类不是从theropod进化来的
B中的内容是作者提出的，科学家对于lung这一点只是提出质疑lung并没有说evidence的事情

第一过完必须要谨慎，第二突然出现的代词要找到先行词

第三題: Ad revenue (in $) per dollar charged for advertising impressions
CPM=1(per dollar charged)=Ad Revenue / (Readership * Pages)
因此Ad Revenue=Readership * Pages，找Readership*Pages最大(即revenue最大)

B are subjected to; as + n 作为的语义
C as错

注意题中有提示being China's first administrators；their empire所以要用复数

在逻辑上，限制传播的是复数名词fierce intercolony struggles，而不是单数名词kind。 kind是种类的意思，种类不会限制传播。

A 试图通过一个变化对当前成员的影响 来推断对潜在成员的影响。当前的菜鸡们没能力做讲座，不代表最优秀的候选人不做讲座。
E 假定对大部分成员有益的变化将对所有成员都有益。P并没有对有益的涨工资部分进行反驳，而是对有害的禁令进行了反驳，所以不对。

在动物园会感染的员工会转业，那么留下来的都是不太容易感染的了，不容易被感染的人的可能有30%，那么动物园外的普通人感染概率就高了

D if recognized and applied, students 句中主语是学生 语义是如果被学生被认知和使用 不符合逻辑。注意看啊！因为if后面是一个完整的句子和前面句子的主语是不一样的不能公用下来！！

D平行不正确

After the islands separated, the isolated lizard populations would have become distinct species while also retaining their ancestors' niche adaptations.

我理解B是省略，但不省略的话，应该是什么呢？a greater proportion than that was？

D 取非之后说的是 会惩罚第一次没有做好（导致 later had to be reworked）的工人。如果是这样的话，工人应该第一次就更加认真做（应该不想被罚款），那么第一次的满意度更好才对！但是这样想就质疑前提了，因为文章结论的Premise是“When initial repairs are inadequate”。总的来说D 和我们想要削弱这个原因（工作复杂需要二次返工）没关系。

A选项师生比例高是削弱，且A选项用过去的信息未必能类比到将来