ron:"twice as many", "one-quarter as many", etc. are not only acceptable as idiomatic expressions but also extremely common in the english language.
since this idiom is present in the correct answer, which was written by gmac, IT IS CORRECT.
end of discussion.

amount ==》n .通常去修饰不可数名词（但是amount这个词本身是可数名词的）==》 a large amount of work, money, furniture //
Food was provided in varying amounts.
amount也可以用作v.总计 达到 Our information doesn't amount to much 我们的资料有限

drive-in n. 免下车餐馆,免下车电影院 drive-ins 是复数了...
at the height of sth 在sth的鼎盛时期

shelter: intransitive verb
«person, animal» 躲避 duǒbì
▸ to shelter from the storm
躲避暴风雨
▸ to shelter under a tree
躲在树下

The culprits for service-sector productivity stagnation are the forces—such as corporate takeovers and unnecessary governmental regulation—that distract managers from the task of making optimal use of available resources.

stagnation——improvements 取非

if budget deficit were lower, interest rates would be lower too, thereby increasing investment in the development of new technologies, which would spur productivity growth in the service sector.
discrepancy: in productivity growth between the manufacturing and service sectors.

communal=community as a whole

注意从句的修饰！！不是N是3的倍数，而是原来这个数

1. fewer and less区别
2.amount 不可数

补充 as many 的用法

1. as many的用法(摘自Longman):
as many=a number that is equal to another number 表示同样的数字
They say the people of Los Angeles speak 12 languages and teach just as many in the schools.
in as many days/weeks/games etc.
A great trip! We visited five countries in as many days (=in five days).
*: "twice as many", "one-quarter as many", etc.都是非常常见的用法，记住这样的表达。

这道题最开始做的时候 完全是 主观臆断的排除了cde...只留下了ab ...

当想用being+adj的时候 一定要先去想一下是不是有更好的表达方式==》定语从句 / v-ed / 直接的adj修饰 / 同位语修饰

① , despite being offered $1,000 to do so.《==注意看 显然这个修饰需要main clause的主语直接就是那个人
②since so存在语义重复
③you should avoid "being" when expressing the IDENTITY or CHARACTERISTICS of some individual or thing.
otherwise, evaluate it on the same merits as you would any other verb

ron： first, i'm about 99% sure that we are not allowed to use "ones" to refer to people.

second, i'm also about 99% sure that "THE ones" must refer back to "THE some other noun".

注意：however 、 then 、 therefore 、 in addition 都是副词不作连词用

注意：however 、 then 、 therefore 、 in addition 都是副词不作连词用

注意：however 、 then 、 therefore 、 in addition 都是副词不作连词用

bcd都缺动词，a和e杀e

"an isolation that limited both cultural contact and exposure to European diseases. " 直接提到了 limit.
"it was a period of diminution in population and pressure from contact with outside groups,"提到了 it's a period of diminution of in population and (a period of) pressure from contact with outside groups; 暗示了 did not eliminate。 原来的理解有偏差，事实上在period的大环境下，Hopis难以独善其身，势必也受到影响，只不过影响更小

Confirming that the shungite genuinely（严谨地） contained fullerenes took careful experimentation. 确认石墨包含富勒烯需要经过严谨实验，无关选项
Some fullerenes have also been found on the remains of a small meteorite（陨石） that collided（相撞） with a spacecraft. 有一些富勒烯在陨石和飞船相撞的残骸上被发现，so what？并没有提出lab和nature的区别
The mineral shungite itself contains large amounts of carbon, from which the fullerenes apparently formed. 石墨有大量的碳，这是富勒烯形成所需要的

The naturally occurring fullerenes are arranged in a previously unknown crystalline structure.自然形成的富勒烯有着和之前不知道得晶状体结构，提出lab和nature的区别
Shungite itself is formed only under distinctive conditions.石墨本身生成的条件非常严格，无关