Many companies in the pollution-control industry, which until a few ye

IMO, this is not a valid example . It is just not about SVA alone but there is also an element of comparison in it. In the original, we are comparing performance of the industry until few year’s ago with the performance of the companies recently. This shift of object is illogical. Per se, logically speaking, the companies, the subject of the clause, do two functions; first, they did well earlier and then have not not so well recently. If we mean to describe the industry’s profits, thenwe can straight away start with the industry, dropping the reference to the company’s altogether.

IMO, this is a faulty topic and no choice is tenable

C for me.

Here is my logic.

First there is a SVA issue. Companies in the pollution control industry....have recently experienced.. So it needs to be have instead of has - this eliminates A, D, and E.

We read choice b and see that when prospering is incorrect - should be was prospering to be in SVA with the sentence. So that leaves us with only C.

Hope that helps.

Here's the official explanation provided by the GMAC for this question:

According to the sentence, the pollution-control industry prospered until a few years ago, because of a national concern for environmental controls. Recently, however, many companies in the industry have suffered a sharp decline in sales and profits. The version given is not correct; for one thing, the verb phrase has recently experienced is singular, whereas its subject, many companies, is plural. Also, the verb-form has prospered normally indicates a past action extending into the present or recent past, not applicable here.

Option A: This answer choice is incorrect, for the reasons explained. The preposition on account of has because of as one of its meanings.

Option B: The word up is unnecessary and informal. Overall, this version is incoherent because it implies that the companies experienced reduced sales and profits when prospering. Moreover, this version consists only of a noun phrase many companies … industry following by a relative clause modifying that phrase, together with an embedded adverbial clause when … controls. In other words, this is not a proper sentence because it has no independent clause.

Option C: Correct.The past-continuous verb form was prospering is appropriate here. The present-perfect plural verb form have … experienced agrees with the plural subject companies and is appropriate for describing a recent experience that may be continuing into the present. The use of because of introduces a description of a cause.

Option D: The word up is unnecessary and informal. Because of the plural verb have in the relative clause which … controls, the clause applies to many companies rather than to the pollution-control industry. The singular verb has should also be plural to agree with the same subject.

Option E: The singular verb has is incorrect because its subject many companies is plural.

The correct answer is C.

Please note that I'm not the author of this explanation. I'm just posting it here since I believe it can help the community.

The first logic is correct ie the options will end with 'have'.
But for SVA shouldnt it be 'many companies...were prospering...'? IMO the option doesnt match up.
Am I right?
Also, where is this question from?

Posted from my mobile device

Hope that helps.[/quote]
The first logic is correct ie the options will end with 'have'.
But for SVA shouldnt it be 'many companies...were prospering...'? IMO the option doesnt match up.
Am I right?
Also, where is this question from?

Posted from my mobile device [/quote]



This is where i also got confused. Seems like the 'were prospering' modifier is for the industry. It wasn't intuitive or explicit.

I got these questions from the Jamboree question bank

Subject-verb agreement
and thank you hinkin
when {When is used in reference to a specific time not a period}

Many companies in the pollution control industry, which until a few years ago has prospered on account of a national concern for environmental controls, has recently experienced sharp drops in sales and profits.

plural subj needs plural verb

the modifier is more clear here

hi bibli, what is the source of this qn?

Many companies in the pollution control industry, which until a few years ago has prospered on account of a national concern for environmental controls, has recently experienced sharp drops in sales and profits.

In above the c answers the question correctly. SVA issue leaves us with just B and C. Out of the two C is correct since the was refers to singular Pollution Control industry and have correctly refers back to Many Companies.

Answer C

Choice A - SVA error
Choice B - Up until incorrect usage
Choice C - Correct usage of both verbs
Choice D - Up until incorrect usage
Choice E - incorrect verb

the 'which' takes the immediate preceeding noun i.e. 'control industry' -> hence 'was' is correct

Correct option C

Original Sentence
Many companies in the pollution-control industry, which
until a few years ago has prospered on account of a national concern for environmental controls, has
recently experienced sharp drops in sales and profits.

B. up until a few years ago, when prospering on account of a national concern for environmental controls, have
Error:
- Redudancy "Up untill" & "when Prospering" both indicate "Growing"
- Idiom placement Error "on account of", it should reflect reason for prospering

C. until a few years ago was prospering because of a national concern for environmental controls, have - Correct

Eliminate A, D and E - SV Agreement Error
A. until a few years ago has prospered on account of a national concern for environmental controls, has
D. up until a few years ago have prospered because of a national concern for environmental controls, has
E. until a few years ago had prospered because of a national concern for environmental controls, has

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