OG119, 请解答

119. Executives and federal officials say that the use of crack and cocaine is growing rapidly among work­ers, significantly compounding the effects of drug and alcohol abuse, which already are a cost to busi­ness of more than $100 billion a year.

(A)  significantly compounding the effects of drug and alcohol abuse, which already are a cost to business of

(B)   significantly compounding the effects of drug and alcohol abuse, which already cost busi­ness

(C)  significantly compounding the effects of drug and alcohol abuse, already with business costs of

(D)  significant in compounding the effects of drug and alcohol abuse, and already costing busi­ness

(E)   significant in compounding the effects of drug and alcohol abuse, and already costs business

答案是B， 请问B在句中做什么成分，分词结构就近修饰名词还是句子的主语，分词的这一用法总是不太清楚，另外WHICH为什么修饰EFFECTS而不是修饰ALCOHOL ABUSE呢

请帮忙，谢谢

119. Executives and federal officials say主句

that the use of crack and cocaine is growing rapidly among work­ers, 宾语从句（从1）

significantly compounding the effects of drug and alcohol abuse, 主句宾语(从1）的同位语（从2）

which already cost busi­ness more than $100 billion a year. 从2的非限定定语从句（从3）

分词结构修饰谁取决于它做什么成分，一般情况下如果是作同位语，主语同位语在主语前/后，作宾语同位语在句尾。但是与被修饰词在句中的位置无关。这道题里分词结构作的是宾语从句的同位语。

the effects of drug and alcohol abuse 中心词是the effects 所以which的先行词是它。后面of介词词组可以忽略不看。

B中compounding修饰前面一句话 ，也就是分词可以修饰前一句话的中心意思。对于which到底修饰谁，还要看逻辑意思。并不是说就近修饰的。如

1.        From the bark of the paper birch tree the Menomini crafted a canoe about twenty feet long and two feet wide, with small ribs and rails of cedar, which could carry four persons or eight hundred pounds of baggage so light that a person could easily portage it around impeding rapids.

which修饰的是canoe而不是rails 或cedar。

with samll ribs and rails of cedar是个插入语,which从句基本还是符合就近修饰的原则修饰前面的先行词canoe.

个人看法，with small ribs and rails of cedar是方式状语，表明Menomimi crafted a canoe时所用的原材。

请指正！

有了逗号的话，which XXXX修饰abuse的力量是不是就弱了些？如果没有逗号是不是就会有confuse之嫌?

我的想法是which 是邻近指代, 不管有无逗号都无所谓了, 这里要看which 后的谓语单复数, 若用 costs, 则明显的是修饰abuse, 造成歧意,

而我理解的是若是状语无逗号,则必定是修饰其前的名词......., 而有逗号则可能修饰主语, 或其前的名词..

有更完整的意见吗? 一点拙见敬请指教

c)...,already with business cost of more than 100 billion a year

它\是独立主格, 所以缺乏修饰前面的effects对吧, 因而造成意思不清

那句子的状语到底何时会修饰句子中的其他名词呢?