" carbon dioxide 不可数 必须用less修饰 other gases可数 用fewer修饰，排除CDE

as well as做介词，主句为简单时态sb do sth，后面动词通常用doing，如：He sings as well as playing piano.他会唱歌以及弹钢琴。
如果有情态动词或助动词，后面动词用原型，He can sing as well as play piano.
前面是to do时，后面用原型。He want to sing as well as play piano."

AB判断——结合语义
【燃烧更少的化石燃料】和【释放更少的CO2】是伴随发生关系还是并列发生关系？答案是伴随。——状语表伴随

本题在ＡＢ之間糾結，注意 as well as 不是并列连词，FANBOYS才是。
根据伴随的核心概念「两件事情几乎同时发生」，燃烧更少fuel和排放更少气体几乎是同时发生（燃烧就排放了），所以要选Ving伴随，而不是两件事情

carbon dioxide gas不可数，gases可数，分别对应less和fewer，排除CDE
“燃烧更少汽油”和“排放更少gas”是因果关系，用伴随更合理
A correct

语义上他们是存在同时发生关系的，用as well as doing是对的

(A) I can’t complain about this one. “Carbon dioxide gas” is a singular, non-countable noun, so “less” works fine as a modifier. And this part is a little bit tricky, but the second part of the sentence refers to several different “gasses” – a countable, plural noun – so “fewer” is appropriate.

The phrase beginning with “that” (“that have been implicated…”) correctly modifies “other gasses.” It’s also completely fine to use the “-ing” form of the verb after “as well as.”

So we’ll keep (A).


(B) It’s a funny quirk of English: if “as well as” were changed to “and” then we’d want the verbs “burn” and “emit” to be in parallel form. But since we have “as well as”, we’re better off using “emitting”, as we did in (A).

More importantly, I can’t make any sense of the “having been” at the end of the underlined portion. For that reason, we can scrap (B).


(C) You could argue that the pronoun “they” is ambiguous here, since it could refer to “diesel engines” or “gasoline engines”, but I’m not convinced: since “they” is the subject of the second clause, it can generally refer back to the subject of the first clause on the GMAT without causing any trouble.

But we definitely have a modifier problem here: “fewer carbon dioxide” doesn’t make any sense, since “carbon dioxide” is a non-countable noun, and “fewer” can only be used with countable nouns. (If you’re not clear about that concept, try counting the noun out loud: “one carbon dioxide, two carbon dioxides, three carbon dioxides…” That makes no sense at all, right? So “carbon dioxide” is non-countable.)


(D) The first part of the underlined portion isn’t necessarily WRONG, but it definitely isn’t great: “gasoline engines that have a comparable size” is a really crappy way to say “gasoline engines of comparable size.” I just don’t think it makes sense to use the word “have” in this context, since gasoline engines don’t really possess size.

More importantly, we have a problem with the non-countable modifier “less”, since it seems to be modifying both “carbon dioxide gas” (non-countable) and “other gasses” (countable) – and “less” can’t modify a countable noun.


(E) The first part of the underlined portion suffers from the same problem as (D): “that have a comparable size” is a lousy way to say “of comparable size.” But again, I wouldn’t necessarily eliminate (E) based on that issue by itself.

The other problem is the same as in (D): “less” seems to modify “other gasses”, and that doesn’t work. Plus, I’m really not sold on the idea of using “having” to modify “gasses” at the end of the underlined portion – the version in (A) (“gasses that have…”) seems a little bit better.

from this example, you can learn that 'as well as' is not strictly a parallel marker.incidentally, in the official correct sentences, i've never seen 'as well as' followed by anything other than a noun. (remember that '__ing' can be a noun; that's the role played by 'emitting' here.)

i wouldn't elevate this to the status of a 'rule', since as well as is also widely used to connect other things, such as adjectives (His review was insightful as well as thorough).

on the other hand, i am comfortable positing these two things:
• don't follow 'as well as' with a verb
• be suspicious of any choice in which 'as well as' is followed by something other than a noun. (if you can't see any other reason to eliminate, use this as a guessing method.)

1、BE "having __ed" (without a comma)不选，havedone表完成，ving现在进行，放在一起说不通；
2、as well as 作为介词，常跟n.&adj.&prep.&doing, 有主次之分；as well as 结构去掉后，句子结构仍然完整；
3、CDE carbon dioxide gas不可数名词，用less修饰；other gases 可数名词，用fewer修饰；
4、语义：【燃烧更少的化石燃料】和【释放更少的CO2】是平行关系还是主次关系，应该是主次。

far less carbon dioxide gas and far fewer of the other gases 前面不可数后面可数
仔细读题

燃烧更少的燃料同时释放更少的CO2 o(╥﹏╥)o

D，they emit far less carbon dioxide gas and other gases 意思是他们排放更少的CO2，他们排放其他气体，因为less不能修饰复数名词gases.

as well as可以看成是介词，介宾作状语或定语，所以as well as连接的东西地位较主句弱。

A/C，燃烧更少的化石燃料和释放更少的CO2是伴随发生关系还是并列发生关系，答案是伴随。as well as emitting做伴随状语，燃烧更少的化石燃料，伴随着释放更少的CO2，ok。

1.incidentally, in the official correct sentences, i\'ve never seen \'as well as\' followed by anything other than a noun. (remember that \'__ing\' can be a noun; that\'s the role played by \'emitting\' here.) as well as是介词，后面通常接名词（Ving也是名词形式）
2.having done (without a comma) 永远不对，因为完成时态表示一个永久的状态，而Ving表示一个暂时的状态，二者矛盾

as well as做介词，主句为简单时态sb do sth，后面动词通常用doing

形容词+of，表示主观的性质或某种状态的对象：it’s nice of you to do sth，fewer of gases

as well as做介词，主句为简单时态sb do sth，后面动词通常用doing，如：He sings as well as playing piano.他会唱歌以及弹钢琴。
如果有情态动词或助动词，后面动词用原型，He can sing as well as play piano.
前面是to do时，后面用原型。He want to sing as well as play piano.

此题看后半截选a， far less carbon dioxide gas and far fewer of the other gases

as well as做介词，主句为简单时态sb do sth，后面动词通常用doing，如：He sings as well as playing piano.他会唱歌以及弹钢琴。
如果有情态动词或助动词，后面动词用原型，He can sing as well as play piano.
前面是to do时，后面用原型。He want to sing as well as play piano.
E，二氧化碳时不可数名词，用less不用fewer

of comparable size和that have comparable size都是做定语成分描述属性，因此一样的。

incidentally, in the official correct sentences, i\'ve never seen \'as well as\' followed by anything other than a noun. (remember that \'__ing\' can be a noun; that\'s the role played by \'emitting\' here.)

i wouldn\'t elevate this to the status of a \'rule\', since as well as is also widely used to connect other things, such as adjectives (His review was insightful as well as thorough