时态错了，选了has been
ron：the past time is implied in the context -- it's whenever we made the discovery that human activities can affect the ozone layer.

Ron：
(1) I get mail from cities as far away as Providence.
(2) I get mail from cities that are as far away as Providence.
If I'm in San Francisco, then sentence #2 means, strangely enough, that I get mail from cities that are all exactly 3,082 miles away (the distance from SF to Providence). Sentence #1 implies no such thing.

没注意到是混合动力车。。。

该句的核心是 the United States acquired 828,000 square miles，带来的结果是 doubling its size and bringing...不能将bringing降级。

同意lizzyfly对于C选项的解释“-ing表示伴随的动作或伴随的结果，resulting from接原因，两种情况都不符合，不能做伴随状语，只能做定语”
同样，伴随状语是修饰主句的动词，并非修饰名词

所以。。。。truck不属于vehicle。。。。？

这个题。。。真的学多了容易做错

are not both odd 读题错

这里是两个时间段的比较，所以 disturbing 和compelling的时态不应该是一样的
i can run faster than my father.
--> this implies that i can run faster than my father can run right now.
i can run faster than my father [i]could (when he was young).[/i]
--> this is how we compare two things that happened in different timeframes.

和with无关，而是逻辑意思 the problem with (a) is that it says only that companies are aware "that there are connotations". in other words, literally, the companies just know that there are connotations -- in other words, that connotations (of some sort) exist -- but the companies don't necessarily know what those connotations are.
i am aware that discounts are available this weekend. 知道有discount这件事，但不知道具体
i am aware of the discounts available this weekend.

A vs D
The budget for education reflects the administration's demand （that）the money （should）be controlled by local school districts, but it（budget） allows them （school districts）to spend the money only be spent on teachers, not on books, computers, or other materials or activities.
A：but后面是完整句，所以只能和主句平行，it无指代
C：but allowing的逻辑主语错误
D：不确定原因
E：it can only spend （it无指代）

A vs B
since releasing伴随状语--- 需要逻辑主语

C vs D
并列： was excited and predicted

so as to要求so前的主语和as to身后动作的主语相同。例如：
I set up the computer so as to do my work. （我把电脑设置好以便完成我的工作）
此时，do my work的主语必须是I。

It would be hard to use X is unable to be Y-ed correctly.

The passive voice and the past participle suggest that something is done (or not done) to X. But the able/unable suggest that X does (or does not) do something. Too abstract? OK, let's get down to the case at hand. Here's the wrong answer you asked about.

we start to have trouble when using "not" with "enough". although it makes sense to say that i am tall enough to reach the ceiling, it's much trickier to assert that i am short enough NOT to reach the ceiling. there are lots of ways i could avoid reaching the ceiling without having to be short..
the takeaway here is that you should be wary of a construction that combines "enough" with "not" in this way..

"enough" usually means that something has a sufficient amount of a property that it can achieve some goal that was otherwise unattainable. for instance, perhaps i am tall enough to reach the ceiling. if i weren't tall enough, i could not reach the ceiling..

there's nothing redundant about "and also".

"and also" is redundant if it appears in the same sentence as "both"; this may be what you're thinking about.

i.e.,
X and also Y --> totally fine
both X and also Y --> redundant (and therefore incorrect)

"as well as" is NOT a replacement for "and".

“A leading figure in the Scottish Enlightenment是同位语，显然应该是修饰一个人的，而不是“书”，”

* if you say "subject + clause + BY VERBing", then "by VERBing" must explain HOW the main clause occurred.
i prepared for the test by reviewing takeaways on the MGMAT forums.
* if you say "subject + clause + IN VERBing", then subject + clause must be an ACTUAL PART of the action of VERBing.
i solved all the problems in OG12 in preparing for the GMAT.