About 5 million acres in the United States have been invaded by leafy

a student recently asked me about this question.

this question serves well to illustrate one of the most important features of GMAT SC: if you stay focused on FUNDAMENTALS — and stay aware of the common-sense INTENDED MEANING of the sentence (which you should always figure out as the very first step of any SC problem), you'll be able to solve the vast majority of SC problems — even the "hard" ones — without needing to consider anything beyond those basics.

for this problem, all we need is overall structure, parallelism, and the usage of comma + __ing modifiers (= the single most commonly tested type of modifier in GMAT SC).

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OVERALL STRUCTURE:

the cue to think about overall structure is the difference between "HAVE been invaded" (a VERB), in choices A/B/C, and "HAVING been invaded" (a MODIFIER), in choices D/E.
(if you see this kind of difference, then one version MUST be wrong. if the verb works, then the modifier will create a sentence fragment with no verb; if the modifier works, then the verb will create a run-on sentence with two verbs "stuck together".)

here, choices D/E are not sentences — they're fragments, with no main verb.
eliminate these.

choices A/B/C, on the other hand, ARE constructed as legitimate complete sentences.

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PARALLELISM & COMMA __ING modifiers:

each of choices A/B/C puts different elements in parallel. these choices also construct the comma + __ing modifier differently.
to decide which version is correct, we'll need to appeal to common-sense meaning.

CHOICE A:
in this choice, the comma + __ing modifier has two parts (which are written in parallel): "displacing grasses and other cattle food and rendering rangeland worthless".
this modifier implies that BOTH of these __ing's modify "gives mouth sores to cattle" (the action of the preceding clause).
this is NONSENSE — it's clearly not possible for "displacing grasses and other cattle food" to be any sort of reasonable description or immediate consequence of the mouth sores.
eliminate.

CHOICE B:
this choice puts two actions in parallel: "gives mouth sores to cattle and displaces grasses and other cattle food". also, comma + "rendering rangeland worthless" modifies "displaces grasses and other cattle food" (= the preceding action).
all of this MAKES SENSE!
• the parallel verbs are two DIFFERENT/SEPARATE things that leafy spurge does;
• "rendering rangeland worthless" is an IMMEDIATE CONSEQUENCE of the displacement of food, and thus makes sense as a modifier of that action.
CORRECT ANSWER

CHOICE C:
this choice puts two modifiers in parallel: "having milky sap that gives mouth sores to cattle and displacing grasses and other cattle food".
this is NONSENSE.
in this sentence, the parallel elements SHOULD be the TWO ADVERSE ACTIONS of leafy spurge:
• it gives mouth sores to cattle,
• it displaces cattle food.
these items are NONparallel here. instead, this choice uses a parallel structure to connect two items that just don't make any sense as "two bullet points".
eliminate.

Hello Everyone!

Here is another great sample GMAT question! Let's take a closer look at each option and see where we can narrow things down to find the right answer! First, here is the original sentence, with any major differences highlighted in orange:

About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.

(A) States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering
(B) States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering
(C) States have been invaded by leafy spurge, a herbaceous plant from Eurasia having milky sap that gives mouth sores to cattle and displacing grasses and other cattle food, rendering
(D) States, having been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displaces grasses and other cattle food, and renders
(E) States, having been invaded by leafy spurge, a herbaceous plant from Eurasia that has milky sap giving mouth sores to cattle and displacing grasses and other cattle food, rendering

There are a couple major differences we can see after a quick glance over the options:

1. have been invaded vs. having been invaded
2. parallel structure

Let's start with #1 on our list because it will eliminate either 2 or 3 options right off the bat: have been invaded vs. having been invaded.

If we read through each option and look for the complete sentence within it, we find a problem:

(A) About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.
(B) About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering rangeland worthless.
(C) About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia having milky sap that gives mouth sores to cattle and displacing grasses and other cattle food, rendering rangeland worthless.

Options A, B, & C are OK so far because there is a complete sentence somewhere in there, with just a few added phrases after it to add detail.

(D) About 5 million acres in the United States, having been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displaces grasses and other cattle food, and renders rangeland worthless.

This option is INCORRECT because, while you could argue there is a complete sentence here, it is vastly different than the intended meaning! The leafy spurge does all of these things, not the land itself!

(E) About 5 million acres in the United States, having been invaded by leafy spurge, a herbaceous plant from Eurasia that has milky sap giving mouth sores to cattle and displacing grasses and other cattle food, rendering rangeland worthless.

This option is INCORRECT because there is no other phrase here that has a verb to complete the rest of the sentence! Therefore, this is one very long sentence fragment!

We can eliminate answers D & E because using the phrase "having been invaded" creates either a sentence fragment or distorts the original meaning.

Now that we're left with options A, B, & C, let's tackle #3 on our list: parallel structure.

We know that leafy spurge does 3 things:
1. gives cattle mouth sores
2. displaces grass and other cattle food
3. renders rangeland worthless

In some options, all 3 items are listed as happening at the same time (A, B, and C). For those, all 3 items must use parallel structure.
In other options, only 2 items are listed, and #3 on the list happens as a result of #1 and #2 (A and B, causing C). In that case, only #1 and #2 on the list must be parallel.

Let's see how each option stacks up in terms of parallel structure:

(A) States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering

This option is INCORRECT because the listed items don't use parallel structure. In this case, the sentence lists all 3 items as happening at the same time, so all 3 must be parallel!

(B) States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering

This option is CORRECT! The two items (gives mouth sores / displaces grasses) use parallel format. The word "rendering" doesn't need to be parallel to the other two here because it is being used to indicate that #1 and #2 on the list lead to #3 happening, so it's okay to keep it the way it is.

(C) States have been invaded by leafy spurge, a herbaceous plant from Eurasia having milky sap that gives mouth sores to cattle and displacing grasses and other cattle food, rendering

This option is INCORRECT because the two items (gives / displacing) need to be in parallel format!

There you go! Option B is the correct answer because it uses parallel structure where needed, and includes a verb to make it a complete thought!


Don't study for the GMAT. Train for it.

I am not an expert, but the way I understood the question is "leafy spurge" has 2 negative effects - it gives mouth sores to cattle and also displaces grasses and other cattle food. As far as I understand in option A the intended meaning is that it gives mouth sores to cattle and, by doing that, displaces grasses and other cattle food.

Dear Friends,

Here is a detailed explanation to this question-
Meaning is crucial to solving this problem:
Understanding the intended meaning is key to solving this question; the intended meaning of this sentence is that 5 million acres in the United States have been invaded by leafy spurge, which is a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, and a result renders rangeland worthless.

Concepts tested here: Meaning + Modifiers

• The introduction of present participle ("verb+ing"- “displacing” and “rendering” in this case) after comma generally leads to a cause-effect relationship.
• If a phrase is subordinate to another in terms of importance (or sharing a cause-effect relationship), the phrases do not maintain parallelism.
• Statements of universal fact are best conveyed through the simple present tense.
• A list separated by commas represents similar elements.

A: This answer choice alters the meaning of the sentence through the construction "displacing grasses and other cattle food"; the use of the "comma + present participle ("verb+ing" - "displacing" in this sentence) and parallelism between a cause ("displacing grasses") and effect ("rendering rangeland worthless") illogically implly that the milky sap gives mouth sores to cattle, and as a result displaces grasses and other cattle food and as a separate action renders rangeland worthless; the intended meaning is that the milky sap gives mouth sores to cattle and as a separate action displaces grasses and other cattle food, and as a result renders rangeland worthless; please remember, the introduction of the present participle ("verb+ing"- “displacing” and “rendering” in this case) after comma generally leads to a cause-effect relationship, and if a phrase shares a cause-effect relationship with another, they do not maintain parallelism.

B: Correct. This answer choice acts upon the independent noun "acres" with the active verb "have been invaded" to form a complete thought, leading to a complete sentence. Further, Option B uses the phrase "and displaces grasses and other cattle food, rendering rangeland worthless", conveying the intended meaning - that the milky sap gives mouth sores to cattle and as a separate action displaces grasses and other cattle food, and as a result renders rangeland worthless; please remember, the introduction of the present participle ("verb+ing"- “rendering” in this case) after comma generally leads to a cause-effect relationship. Moreover, Option B correctly avoids parallelism between a cause ("displaces...cattle food") and its effect ("rendering rangeland worthless"). Additionally, Option B correctly uses the simple present tense verbs "gives" and "displaces" to refer to statements of universal fact.

C: This answer choice incorrectly uses the present participle ("verb+ing" - "displacing" in this sentence) to refer to a statement of universal fact; please remember, statements of universal fact are best conveyed through the simple present tense. Further, Option C incorrectly maintains parallelism between a cause ("displacing grasses") and effect ("rendering rangeland worthless"); please remember, if a phrase shares a cause-effect relationship with another, they do not maintain parallelism.

D: This answer choice fails to form a complete sentence; as "having been invaded" is a noun modifier, there is no active verb to act upon the subject noun "acres". Further, Option D alters the meaning of the sentence through the phrase "gives mouth...displaces grasses...,and renders rangeland worthless"; including these three actions in a list together incorrectly implies that the milky sap gives mouth sores to cattle, displaces grasses and other cattle food, and renders rangeland worthless, as three separate actions; the intended meaning is that the milky sap gives mouth sores to cattle and as a separate action displaces grasses and other cattle food, and as a result renders rangeland worthless; please remember, a list separated by commas represents similar elements; in this case, the three phrases involved have different roles in the correct meaning of the sentence.

E: This answer choice fails to form a complete sentence; as "having been invaded" is a noun modifier, there is no active verb to act upon the subject noun "acres". Further, Option E incorrectly uses the present participle ("giving" and "displacing" in this case) to refer to statements of universal fact; please remember, statements of universal fact are best conveyed through the simple present tense.

Hence, B is the best answer choice.

To understand the concept of "Simple Tenses" on GMAT, you may want to watch the following video (~1 minute):



To understand the concept of "Comma + Present Participles for Cause-Effect Relationships" on GMAT, you may want to watch the following video (~3 minutes):



All the best!
Experts' Global Team

could anyone explain how A is wrong?

My line of thoughts:
a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle
appositive for leafy spurge.

The sentence, after removing above appositive is correct:
About 5 million acres in the United States have been invaded by leafy spurge, displacing grasses and other cattle food and rendering rangeland worthless.

In B , it seems like "that" is pointing to Eurasia not milky sap..
If B is correct,can some please justify usage of that here..

Comma + that is worrying me in option B ...

Posted from my mobile device

Thanks for your reply, @Verdan95. I, still, feel like "displacing grasses and other cattle food and rendering rangeland worthless." modifies "leafy spurge".
If you remove the appositive in red below, the sentence read correctly to me.
About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle, displacing grasses and other cattle food and rendering rangeland worthless.

The question checks the meaning and parallelism.

Parallel elements are
gives mouth sores to cattle
displacing grasses and other cattle food and
rendering

Here the leaf spurge performs two actions
gives mouth sores to cattle
displace grasses and other cattle food

The effect of the second action(displace grasses and other cattle food) causes the third rendering rangeland worthless.


So rendering rangeland worthless is a modifier, not an action
So B is the correct option
The other option either considers three parallel elements or causes meaning ambiguity

Hello sobby,

I would be glad to help you resolve your doubt.

Let me bring in here the sentence with Choice B:

About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering rangeland worthless.

In the above-mentioned sentence, it is the phrase with milky sap that has been enclosed between two commas. If we were to remove this phrase from the sentence, we would also remove the comma before with and the comma after sap. Hence, it is not so that the that clause is preceded by a comma.

The placement of the phrase with milky sap between the two commas implies this is just an additional information. The milky white sap does not necessarily give mouth sore to the cattle. It is the plant that does so.

Now let's talk about how that correctly modifies the noun entity a herbaceous plant. There is no issue in that modifying a herbaceous plant because the phrase from Eurasia modifies a herbaceous plant and cannot be placed anywhere else in the sentence. Here we see the case of a noun modifier modifying a slightly far away noun. We have a detailed article named Noun Modifiers can Modify slightly far away noun that deals with this concept. This article can be reviewed in the following link:
https://gmatclub.com/forum/noun-modifiers-can-modify-slightly-far-away-noun-135868.html


Hope this helps.
Thanks.
Shraddha

Hi Shraddha

I read another related post on this from you:
https://gmatclub.com/forum/verb-ing-mod ... 35567.html

Does this mean that A without comma before verb + ing phrase would have been correct?

About 5 million acres in the United [u]States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle displacing grasses and other cattle food and rendering rangeland worthless.[/u]

in other words, in the above sentense, would "displacing" modify the preceding noun (cattle) or "leafy splurge"? would this sentence be correct?

Excellent explanation, Shraddha. I have a couple of doubts though. I am truncating part of your solution
to lay stress on my doubts.
For choice A, there is no coma before rendering. How did you assume both rendering and displacing as coma + verb-ing modifier
when in fact coma is present only before displacing. Do you assume this because of parallelism?
Also want to understand if my noun + noun modifier is correct in option B: a herbaceous plant (noun) from euracia (noun modfier due to presence of from) modifies
leafy spurge - a noun. Also let me know of you omit phrases between coma to understand meaning better. There are just two many (comas) to complicate things in option B
WR,
Arpit

Hi RaguramanS, this is a very good analysis. The key to this question is to understand that mouth sores to cattle have nothing to do with displacing of grasses.

In fact, parallelism with participial phrases is a very commonly tested concept on GMAT and is totally about understanding the intended meaning of the sentence.

p.s. Our book EducationAisle Sentence Correction Nirvana discusses Parallelism with participial phrases, its application and examples in significant detail. If someone is interested, PM me your email-id; I can mail the corresponding section.

Hello sevenplusplus,


Thank you for the query.


About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia with milky sap that gives[/color] mouth sores to cattle displacing grasses and other cattle food and rendering rangeland worthless.

No, the above-mentioned sentence is not correct because in this one, the verb-ing modifier displacing now modifier the preceding noun cattle.


Hope this helps.
Thanks.
Shraddha

Hello adkikani,


Thank you for the query.


Whenever two comma + verb-ing modifiers make a parallel list, the comma appears only before the first verb-ing modifier. This is a common usage across the GMAT SC section.

And yes, the connector and between displacing... and rendering... is the indicator that since they are part of a list and since displacing... is preceded by a comma, hence rendering... is also a comma + verb-ing modifier.


The phrase a herbaceous plant from Eurasia is not a Noun + Noun Modifier because a prepositional phrase is not exclusively a noun modifier. It modifies either a noun or an action, depending on the context of the sentence.

But yes, a herbaceous plant from Eurasia is a noun phrase that modifies the preceding noun leafy spurge. Again usage of noun phrases to describe a noun entity is common on GMAT SC.

Let's take a look at the sentence with choice B: About 5 million acres in the United States have been invaded by leafy spurge, a herbaceous plant from Eurasia, with milky sap, that gives mouth sores to cattle and displaces grasses and other cattle food, rendering rangeland worthless.

So Arpit, just treat these commas as a pause points to read and understand the sentence better. Of course, the comma before rendering... defines the role of this entity in the sentence. But the other commas are really the pause points so that you can relate all the information properly to understand what the author wants to convey.


Hope this helps.
Thanks.
Shraddha

egmat
I have a question. You wrote " The comma + verb-ing modifier displacing has been turned to simple present tense verb displaces. The comma + verb-ing modifier rendering correctly modifies the preceding action displaces, presenting the result of this action. Because the leafy spurge displaces grasses and other cattle food, it renders rangeland worthless. "
But I thought in correct ssentence "rendering" modifies its previous clause's two actions that are "gives mouth.. " and "displaces". However, from your sentence it seems to me that only "displaces" is the reason.So I feel confused. If two verb are jointed by and, will modifier only modify last verb?!

Posted from my mobile device

Hi Shraddha Thanks for clarification.

I have one question for choice B. "that" after the non-vital modifier "with milky sap" what does it refer to, logically it should refer to leafy spurge. Because in one of my questions, when i chose a choice that had "that" modifier seperated from the noun by a non-vital modifier (as with choice B for the questions), i was marked wrong. So i rejected choice B for this question. I am kind of mis-guided.

Can you please help clarify the concept.

Thanks