OG 11-118 lack的用法问题，求解答

swimswan

118. Students in the metropolitan school district lack mathskills to such a large degree as to make it difficultto absorb them into a city economy becominq ever more dependent on information-based industries.

(A)lack math skills to such a large degree as to make it difficult to absorb them into a city economy becoming

(B)lack math skills to a large enough degree that they will be difficult to absorb into a city's economy that becomes

(C)lack of math skills is so large as to be difficult to absorb them into a city's economy that becomes

(D)are lacking so much in math skills as to be difficult to absorb into a city's economy becoming

(E)are so lacking in math skills that it will be difficult to absorb them into a city economy becoming


OG中对A的解释里面有一句：lack should be are lacking in,这是什么道理？

lonelyorchid

能把OG里关于A的解释的完整版贴一下么？
牛津高阶双解：
lack  
/ læk; læk/ v
[Tn no passive 不用於被动语态] be without (sth); have less than enough of 没有（某事物）; 缺乏; 缺少; 不足: lack creativity, self-discipline, courage 缺乏创造性﹑ 自制力﹑ 勇气 * They lacked the money to send him to university. 他们没钱送他上大学. * What he lacks in experience he makes up for in enthusiasm. 他热心工作以弥补其经验的不足.
[Ipr no passive 不用於被动语态] ~ for sth (fml 文) need sth 需耍某事物: They lacked for nothing, ie had everything they wanted. 他们无所需求（已应有尽有）.
(idm 习语) be `lacking not be available when needed 不敷所需: Money for the project is still lacking. 进行这个项目的钱还没有着落. be lacking in sth not have enough of sth 不足; 不够: be lacking in warmth, courage, strength 缺乏温暖﹑ 勇气﹑ 力气 * The film was lacking in pace. 这部影片不紧凑. have/lack the courage of one's convictions => courage.
> lack n [U, sing] absence or shortage (of sth that is needed) （所需事物的）缺乏, 短缺: a lack of care, money, water 缺乏关心﹑ 金钱﹑ 水 * The project had to be abandoned for (ie because of) lack of funds. 工程因资金匮乏只得放弃.
# `lack-lustre adj dull; uninspiring; lifeless 无光泽的; 死气沉沉的; 无生气的: lack-lustre eyes 暗无光泽的眼睛 * They gave a lack-lustre performance. 他们的演出死气沉沉.

swimswan

OG 的解释：

Rhetorical construction
The underlined portion is so awkward and wordy that it makes the whole sentence difficult to understand. The sentence reveals an ongoing situation (the economy is becoming...), so the use of the present progressive tense (are lacking in) in place of the present tense (lack) is appropriate. The long, awkward modifier to such a large degree as to make it difficult must be simplified and condensed. The idiomatic construction so x ... that can be joined with the progressive verb for greater clarity and economy: Students ... are so lacking in math skills that it will be dcult .. .
A Lack should be are lacking in; the awkward modifier should be condensed by using the so x ... that construction
B Lack should be are lacking in; to a large enough degree that is not a correct idiom; that becomes should be becoming
C The use of the noun lack results in an ungrammatical construction
D So much ... as to be dfficult is not a correct idiomatic expression
E Correct. In this sentence, the present progressive verb are lacking reveals an ongoing situation; the construction so ... that is clear, concise, and correct.

The correct answer is E.

花子落落

OG原话：Additionally, A, B, and C fail to use one or both of the "-ing" forms are lacking and becoming; these forms are preferable to lack and becomes in describing progressive and ongoing conditions.

og 的意思是说lack和become都应该用-ing的形式，lacking是进行时，becoming是分词修饰economy
"fail to use one or both of..."的意思是说“要不就全都没用，要不就只用了一个”，即：
A - fail to use "lacking"
B - fail to use "lacking" and "becoming"
C - fail to use "lacking" and "becoming"

请LZ看http://forum.chasedream.com/GMAT_SC/thread-68452-1-1.html

花子落落

http://gmatclub.com/forum/math-skills-78608.html
这里也有这题的解释

swimswan

谢谢喽