first, examine the split between 'more ergonomic' and just 'ergonomic'. in this case, we must preserve the meaning of the original statement: the new design is more ergonomic than the old design. if we change this to just 'ergonomic', we're attaching an implication that the old design simply wasn't ergonomic (and that the new design, by contrast, is) - an unacceptable implication. that gets rid of answer choices c, d, and e right there.

another item to examine is parallelism. in this case, in the construction 'X rather than Y' (or its analogues, 'X and not Y' and 'more X than Y'), items X and Y must be parallel.
choice a: conforming... rather than flaunting... <-- good parallelism!
choice b: to the body's shape and not to flaunting shape <-- logically nonparallel and also awkward
choice c: can't use 'more' together with 'and not to' (these are exclusive constructions, sort of like 'both' and 'as well as': if you use one, then you can't use the other), so we don't need to consider the parallelism in the first place.
choice d: can't use 'more' together with 'rather than'; also, bad parallelism between to the body's shape and shape flaunted...
choice e: more to the shape... than flaunting... <-- nonparallel

in fact, the winning choice (a) is the ONLY choice that properly compares 'conforming' and 'flaunting' in parallel. all of the other constructions also change the meaning of the sentence via their alterations of the words.

the correct answer here is still pretty ugly, so let's criticize the four incorrect choices.

choice a:
faulty comparison:
'unlike many u.s. cities, ... the river in san antonio...' --> can't compare cities to a river

choice b:
comparison isn't so good:
the second part should start directly with 'the river' (instead of 'in san antonio the river...'), so that the comparison is more clear.
much more importantly, poor use of the relative pronoun 'which':
'...cities in the united states, which is no longer the focal point...'
relative pronouns like which, by default, refer to the noun that's closest to the left, which in this case is the united states. therefore, this relative pronoun is used in a way that's either ambiguous (if you allow it to potentially refer to other nouns) or just plain wrong (if you follow the rule strictly).

choice c:
faulty comparison again
'the river...' is being compared to san antonio.

choice d:
drastic change in meaning
this sentence has completely gotten rid of any reference to the concept of 'no longer'. while all the other sentences say that things have changed, this sentence presents the situation as if it's always been that way.

1、整个句子的时间是in 1997，过去的时间，不能用现在完成时
2、the number jumped to 20%, jump to有跳起来以够到的意思，比jump at好

［比较问题］
如果比较两边时态相同的话，than后面的have确实是可以省略的，但是年轻人和父母爷爷奶奶比，平行过去肯定爸爸妈妈那个时候是过去的情况，所以had是需要补充出来的［时态变了］

CE 区分：逗号+doing做伴随状语是对的，但是including是例外，可以修饰定语
主谓一致，看have， 排除AB
从句中的include修饰tools应该是单数，排除CD

tend to do，to表方向，倾向
bother to do 和 bother doing ，费心/操心做某事
B，they指代错误
选项A（×）：
使用if从句的话，要主将从现，if …… will tend…… 。此处if从句省去主谓， 还原后主语是jay，而不是treat
Can tend ……能往往（语义不通）

as high as 应该接一个具体值，而不是一个范围
some of our players weigh as much as 300-325 pounds --> bad phrasing
some of our players weigh as much as 325 pounds --> good phrasing
a height of——idiom
平行&独立主格

调查的是一个影响，改变是不用调查的，而是观察，排除AD
E，effects后面可看作定语从句，effects做宾语，省略that，但这么写就缺少谓语了
C，for investigating缺少逻辑主语，排除

C和D里边as much错误，要用as many，因为comets是可数名词。

SUBJECT + ACTIVE VERB + BY + NOUN is generally incorrect.**
SUBJECT + ACTIVE VERB + BY + VERBing is generally correct, if "VERBing" is the method or process by which the ACTIVE VERB is carried out.
e.g.
i prepared for the test by studying flash cards --> CORRECT
i prepared for the test by the study of flash cards --> INCORRECT

on the other hand,
SUBJECT + PASSIVE VERB + BY + NOUN is an absolutely fundamental form, if the NOUN is the thing/person that did the action to the SUBJECT.
e.g.
james was seen by two witnesses. --> CORRECT
--
** the only exceptions to this occur in the case of special idiomatic expressions. for instance, "by candlelight" is a known idiomatic expression, so constructions such as "i studied by candlelight" are correct.

D，they无指代

法律类的名词后面加定语一般用doing形式一般不用定语从句
on the ground that ... 以…为理由,以…为借口
on the grounds that prep.由于,以...为理由
on the allegation that ... 理由是…,根据…理由
on the assumption that adv.假设
on the assumption that ... 以为…,假定…

A，becaus后面只能接句子
C，you can't use 'resulting from' as an adverbial modifier, as is done here. in general, 'resulting from' is only used as an adjective modifier, almost always without a comma, as in
the pollution resulting from the chemical spill forced all the local residents to evacuate.
DE：there is nothing wrong with saying 'there is x'. this construction is basically equivalent to 'x exists' (if x is a thing), or 'x happens' (if x is an event).
the problem, though, is that "the intentional discarding of lens caps, packing material , fuel tanks and payload covers" IS the "littering".
so, sentences D and E are not logical.
because of' must be followed by SOMETHING ELSE that is actually the cause of something.
'with' should be followed by a component or part of the previous observation.
note that the correct answer is phrased in a way that removes this problem.
the correct answer says "orbits ... have become more and more littered". in this version, "littered" means roughly the same as 'dirty' or 'polluted'.

笔记-插入语：
1. 形容词或形容词短语作插入语，worst still, sure enough, strange, most important of all等。例句：Strange, there is nobody in the classroom.
2. 副词或副词短语作插入语。personally, honestly, fortunately, luckily, for us, though, besides, exactly, surely, frankly, still otherwise 等。
3. 介词短语作插入语。of course, in short, as a matter of fact, by the way, On the contrary, on the other hand, in my opinion, in conclusion等。
4. 现在分词短语作插入语。generally speaking, judging from/ by ..., talking of..., considering...等。例句：Considering his age, he did very well.
5. 过去分词短语作插入语。例句：Painted white, we like the house better.
解析：之所以称它为插入语，是由于这种过去分词是独立的，没有逻辑主语。
6. 动词不定式作插入语。to be sure, to be frank（坦率地说）,to tell you the truth（说实话）,so to speak（可以说）等。
7. 代词词组作插入语。all the same（尽管如此）,all told（总共）,all in all（总的来说）等。
8. 句子：I say /hear, I think /hope / believe, you know / see, what’s more, that is (to say), I’m afraid, do you think / suppose等。
例句：It’s a great mistake, I think, not to accept their proposal.
9. 从句：if so / not / any, if I may say so, if you don’t mind, as you know, as you say 等。
例句：This man, as you know, is good for nothing.
10. 用标点符号引导插入语。例句：He was (strange as it seems) an excellent sportsman.
the problem with (c) is NOT grammatical; the grammar of (c) is just fine.
the problem with (c) is that it uses two different transitions incorrectly.

* if you say "subject + clause + BY VERBing", then "by VERBing" must explain HOW the main clause occurred.
e.g.
i prepared for the test by reviewing takeaways on the MGMAT forums.
note that the boldface clause describes HOW i prepared for the test.

choice (c) means that using websites, etc. was how the industry organized the campaign -- in other words, they used the websites and public meetings to organize the campaign in the first place. that's an incorrect meaning.
(the campaign ITSELF used these things; the correct modifier in (a) and (b) shows that relationship.)

* if you say "subject + clause + IN VERBing", then subject + clause must be an ACTUAL PART of the action of VERBing.
e.g.
i solved all the problems in OG12 in preparing for the GMAT.
--> notice that solving the problems IS ACTUALLY PART OF preparing for the test.

choice (c) fails here, too, since organizing the campaign (the main clause) is not ACTUALLY PART OF convincing the government.


choice (e) has two problems.

the first is "in convincing", which is wrong for the same reason why it's wrong in choice (c). see above.

the other is incorrect verb tense. "which used" (simple past tense) shouldn't be in a tense occurring prior to "has organized" (present perfect). this construction mistakenly suggests that the campaign "used X, Y, and Z" before it was even organized in the first place.

RON:if you say "twice as many", then this construction should be paired with a countable noun./
e.g., twice as many dogs --> "dogs" is a countable noun/

if you said "twice as much", then this construction should be paired with an uncountable noun./
e.g., twice as much water --> "water" is an uncountable noun/

if the noun in question is already an explicitly numerical quantity, then you should use neither "much" nor "many". instead, you should just use "twice" or "double" by itself./
e.g., twice the increase --> "increase" is an explicitly numerical quantity/

these rules are followed pretty closely./
so, for instance:/
twice as much water --> correct, since "water" is an uncountable noun (but is not an explicitly numerical quantity)/
twice the water... --> incorrect, since water is not a numerical quantity/

twice as much as the increase... --> incorrect; redundant/
twice the increase... --> correct/

引用：这里不能出现任何与former 有关的词，一是因为后面的for 18 years，不能做前主席18年；二是从平行和逻辑一致性考虑，后面的board menber也没用former。这个句子看不出JP到底还在不在位子上，如果要把前主席的意思表达出来，可以用同位语+定语：the former chair of the planning board who was in that position for 18 consecutive years and the former board member working for 28 years, Joan Philkill …… for his duty

initiating，主语只能是California
E，per person和per capita赘余

ome initial considerations:
- the proper idiomatic form with 'made it possible...' is FOR noun INFINITIVE.
- the sentence contains a comparison, so you should be thinking about parallelism from the outset.

choice a:
- 'make it possible ... are able to' is redundant
- i'm not sure about 'compares' as a verb in the active voice here (although i'm not confident enough to give you a straight 'no' on the issue). to me, 'is comparable to' looks better than 'compares to' (although it's possible that both are acceptable).

choice b:
- 'to have' is unclear (who HAS the cameras? the sentence leaves that issue totally unresolved)
- 'at' is unidiomatic (you capture images WITH a degree of fidelity)
- 'with' is not properly parallel (should be 'of')

choice c: CORRECT
- proper idiom: make it possible FOR noun INFINITIVE
- 'with' = proper idiom
- proper, parallel comparison: the DEGREE of fidelity is comparable to THAT (i.e., the degree of fidelity) of 35mm film

choice d:
- change of meaning: the original sentence doesn't assert that the cameras are now possible, but, rather, that existing cameras can be improved.
- improper comparison: this sentence literally compares a DEGREE of fidelity to 35mm FILM (not logically comparable / parallel items)

choice e:
- change of meaning: the original sentence doesn't assert that the cameras are now possible, but, rather, that existing cameras can be improved.
- 'that with' should be 'that of'

more..than，排除AE
单位的比较（grams）用less来描述

(A) 同位语a trend的分词后置定语placing，不能表现出即将发生的趋势，而是表达了一直发生的含义。
(B) correct，用that定语从句修饰同位语trend，清楚地表明了要发生的动作。
(C) which不能指代前面整个句子。
(D) 同位语a trend的分词后置定语placing，不能表现出即将发生的趋势，而是表达了一直发生的含义;it is expected that…的表达不简洁。
(E) which不能指代前面整个句子;it is expected for sb to…的表达不简洁。