定位句：
Clearly price promotions are generally run at a loss, otherwise there would be more of them.
开展价格促销活动是有成本的，否则公司会开展更多价格促销活动。
题目问的是：价格促销活动，对“bottom line 的影响” 的依据是什么。
bottom line 就是盈亏平衡的底线，原文说了开展价格促销活动会增加成本，从而对bottom line影响；如果没有成本，那公司就会开展更多的价格促销活动，
所以价格促销活动的数量和频率 - loss 的变化 - bottom line的影响
这题真是绝了……

老师，不应该是 to deny their permission to participate吗？

increase by 是增长x倍的意思！

并且注意AB选项和C的区别，AB中的中心词在to set dividend 但是C是 be conservative，这也决定了他们省略的词是不一样的

C和D中 to do 和for doing 的区别不用去特别纠结。
Ron说 it is adj. to do
it is adj. for sb. to do
it is adj. that...
均为idiomatic的用法

注意体会 some of which 和 including 带来的含义上的不同

If used to introduce a partial list of something, "INCLUDING" should NOT be considered an "__ing modifier".
In fact, you should think of the word "including", in these contexts, as though it didn't end with "-ing" at all.

comma + "including"...
...elaborates on a NOUN that comes before it (possibly a noun + modifiers);
AND
...is followed by only SOME, NOT ALL, of what that noun encompasses.

B. 1) The phrase “over the past twenty years” seems to talk about the development of the brain from birth to adulthood that took twenty years to develop.
注意：DE均改变了句子重心，所以所有句子的句子重心/修饰 如果A选项没有很大的逻辑问题，那就以A选项中的为主

* "while" MUST be used with a clause or __ing phrase. it can't be used with a construction that doesn't contain any sort of verb form (such as this one, which is just noun + prepositional phrase).

(e) is wrong for a couple of reasons.
* first of all, "with" wrongly suggests that "some" refers not to the colonies themselves but to something that the colonies came with. to suggest that you're referring to the colonies themselves (which you are), you need modifiers of the type used in the correct answer (a).

E中的while很奇怪
在并没有表现①同时进行②表现转折 所以很不合理

注意：出现比较的时候，被省略的部分一定是在原句中present的成分，完完全全一样的成分。
所以一定要补全看！！
DE错在 expect sb that SOV...（第一边做的时候没注意到这个that从句不对）

by contrast, choice (c) is a-ok on this point. this choice also contains "...than they have been (__________)", where the parallel concept, "(more) conservative", actually appears elsewhere in the sentence.

this kills choice (b). that choice ends with "...than they have been", which omits a participle: in other words, it's actually "...than they have been ______", where the ______ is clearly seen to be setting (dividends).
since the EXACT WORD setting doesn't appear anywhere else in this sentence, the sentence is incorrect.

whenever you use a parallel structure with omitted/elided words, the EXACT omitted word(s) MUST be present, IN PARALLEL STRUCTURE, elsewhere in the sentence. this means in exactly the same form - no alterations, no tense changes, no nothing.

b不对的原因是因为文章用的是may 所以语气比较弱吗？？？ Like brown bears and polar bears, sloth bears may have evolved in an environment with few trees.

我觉得可以从反面来推导，假如销售的种类小于10种，比如说有9种，而10%又是最大的销量的话，那么剩下的8种所占的比例是90%，平均下来都大于10%，自然是不成立的。

这道题为什么选C呢？文章中的最后一句有什么深层含义？·

最后despite strained municipal budgets and fading federal support.也不平行啊