某物的数量到底是多还是少并不清楚时，倾向于用numbers，如：
In Scotland, the wild salmon’s numbers have been reduced by uncontrolled deep-sea and coastal netting, by pollution, and by various other threats to the fish’s habitat.三文鱼的数量虽然是一个数字，也用了numbers。
The gyrfalcon, an Arctic bird of prey, has survived a close brush with (A) extinction; its numbers are now five-times greater than when the use of DDT was sharply restricted in the early 1970’s.北极鸟的数量用了numbers
number/numbers:
表示某物的数量，可以说the number of sth，也可以说number/numbers。如：
Los Angeles has a higher number of family dwellings per capita than does any other large city. 这里用number不用numbers，因为每户的住房面积是一个数字而不是很多歌数字。
Upset by the recent downturn in production numbers during the first half of the year, the board of directors, at its quarterly meeting, raised the possibility of adding worker incentives. 因为每个公司的生产指标有很多，所以用复数形式的production numbers.
look at the placement of the modifiers.
"that the bank's loans with..." should immediately follow "the concern", since that is what it modifies.
similarly, "as an obstacle..." should be as close as possible to "cite", because that's what it modifies.
in the correct answer, both of these modifiers are placed immediately next to the things that they're supposed to modify; in (d), both constructions are needlessly separated.
DE if条件状语，不能作为定语修饰drug，错
B whose intended use is for adults and children。也就是drug‘s use is for adults. 这是个主系表结构。在逻辑上，我们只能说，这个药是给成年人和小孩用的，不能说“这个药的用途是对于成年人和小孩的”。
ADE mandate 是BOSSY词，不能接must
ron：the gmat will only do the second of these,so you can rest assured that the personal pronouns (who, whom, he, she, him, her) will be used only for human beings.GMAT里只会考察who指代人，不会考察动物拟人化，所以指代动物时统统用which
as many as 和up to不是考点吗……这题应该用排除法
A they和them指代不同名词
B 分号后要加完整句子
C overturning逻辑主语变成moth而不是bear
D 同样指代错误
E 觉得which有点怪，但"who" is used for humans，sometimes "who" is used for animals that are personified (such as people's pets), but the standard is "which".
rather than和instead of的区别:
语意：rather than表示it's A but not B，instead of表示用一物取代另一物
成分：rather than做连词，表示并列关系；instead of做介词时构成介宾结构，做定语修饰先行词或状语修饰谓语动词，属于修饰成分，地位更弱些。
instead of通常是介词，也可以做连词的，如：They go there on foot instead of by bus.
A,a vantage point combining with her talent for writing to make her the valuable one.
combining with her talent for writing 作定语修饰point，to make her valuable作定语修饰point或作状语修饰动词combine，to表目的，用在此处逻辑不对，不是为了使她成为最棒的那个，而是时间点加上写作天赋的结果是她成为了最棒的那个
B,所有when+某个动作做状语的都需要特别注意，它表示当（且仅当）发生某个动作时，主句才成立。当和她的写作天赋结合在一起时，时间点使她成为最棒的那个，当不和写作天赋结合时，时间点就不能使她成为最棒的那个，但句意没有这个意思，同时也并不是要强调只有和时间点结合时她才是最棒的这件事
I'm going to make air conditioners quieter. --> I'm going to modify existing air conditioners so that they make less noise.
I'm going to make quieter air conditioners.
I'm going to make air conditioners that are quieter.
--> I'm going to make a new model that makes less noise.
A is like the first one of these, so it doesn't make sense in context.
扫描二维码，直接登录
B/D的差异在于D用了so这个连词，将因果的逻辑关系表现得更清楚，优于B“400倍大和400倍远”作伴随状语的表述。