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

Q2) AjiteshArun AndrewN

I am struggling to understand why in B -- another THAT is not required to be explicitly written out ? Is it perhaps because the first THAT is part of the parallel root and thus is enough to apply to the second half [displaces grasses and other cattle food..] ?

[Example : I dont like pets THAT shed and make a mess. Here THAT i am sure applies to bother parts because THAT is part of the parallel root phrase]

In another post From Andrew - Link 1 and and From Ajitesh - Link 2 -- you mention the "THAT" is needed to be written out explicitly if extend has to be made parallel to Is

Why isn't a second THAT needed here but per this linked posts , a second THAT is needed ?

How to reconcile..

Q2) AjiteshArun AndrewN

I am struggling to understand why in B -- another THAT is not required to be explicitly written out ? Is it perhaps because the first THAT is part of the parallel root and thus is enough to apply to the second half [displaces grasses and other cattle food..] ?

[Example : I dont like pets THAT shed and make a mess. Here THAT i am sure applies to bother parts because THAT is part of the parallel root phrase]

In another post From Andrew - Link 1 and and From Ajitesh - Link 2 -- you mention the "THAT" is needed to be written out explicitly if extend has to be made parallel to Is

Why isn't a second THAT needed here but per this linked posts , a second THAT is needed ?

How to reconcile..

Hello sevenplusplus,

I would be glad to help you resolve your doubt.

Let's take a look at the original sentence:

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.

(Blue = subject, Green = verb, Pink = comma + verb-ing modifiers)

Let's understand what the sentence intends to convey. The sentence states that in the US, some 5 million acres of land have been invaded leafy spurge. Describing the leafy spurge, the sentence states that it's a plant from Eurasia. It has milky sap that gives mouth sores to cattle. This leafy spurge displaces grasses and other cattle food and renders rangeland worthless.

However, the way this sentence is worded, it suggests that because leafy spurge gives mouth sores to cattle, it displaces grasses and other cattle food and has rendered rangeland worthless.

We get this illogical meaning from the sentence because of the incorrect usage of the comma + verb-ing modifiers* displacing and rendering.

The comma + verb-ing modifier must modify the preceding action logically and must also make sense with the doer of the modified action.

In this official sentence, the comma + verb-ing modifiers displacing and rendering illogically modifies the preceding action gives by presenting the result of this action. Grasses and other cattle food are not displaced and rangeland are not rendered worthless because leafy spurge gives mouth sores to cattle.

This is the reason why Choice A is incorrect.

From the context of the sentence, we can understand that because leafy spurge displaces grasses and other cattle food, rangeland are rendered useless. So we do have this logical cause-and-effect in the sentence that must be communicated in correct grammar.

Let's evaluate Choice B now:

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.

This choice correctly conveys the logical intended meaning. 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.

*The correct usage of comma + verb-ing has been covered in great details and with pertinent examples in our SC course, In fact, this concept features in the Free Trail course offered by e-GMAT. You can register for free at e-gmat.com and review the concept.


Hope this helps.
Thanks.
Shraddha

Dear Experts,

I read all posts in this forum. But I am still confused (C) and (B).

I can eliminate D & E because
D - It doesn't make sense that an area displaces by itself
E - Fragment
A - Eliminate because displacing and rendering

But I don't understand why C is incorrect. For me, C is better than B

I understand what the sentence intends to convet.
US have been invaded by leafy spurge. Leafy spurge has milky sap. milky sap gives mouth sores to cattle. This leafy spurge displaces grasses and other cattle food. Therefore, These make rangeland worthless

(C) - conveys this meaning.

(B) changes the meaning. Leafy spurge if-self (not milky sap) gives mouth sores to cattle. Also, For me, ", with milk sap, that.... " is awkward.

Could any expert explain me (B) and (C)

Full disclosure: I totally got punked by this one during our last verbal chat. Join us for the next one! https://gmatclub.com/forum/verbal-chat- ... 78-20.html I mean, it's fun to see a guy with an 800 get embarrassed, right? :-D

As some others have pointed out, this one is all about the intersection of structure and meaning. (And there are already some excellent explanations here, but, well, I promised to write one as penance, so here you go.)

I really only notice two things in (A). "That gives mouth sores to cattle" seems to modify "milky sap", and I guess that's OK.

But then at the end of the sentence gives us a pair of parallel "-ing" modifiers, "displacing grasses... and rendering rangeland worthless." And what do they modify?

Hold that thought. We'll come back to that in a second.

OK, so the added commas around "with milky sap" change things just a tiny bit: "that gives mouth sores to cattle and displaces grasses..." now clearly modifies "a herbaceous plant from Eurasia." Hm, that makes a lot of sense.

And now "rendering" clearly modifies the preceding clause, "that gives mouth sores to cattle and displaces grasses and other cattle food." That also makes a lot of sense: rangeland is rendered useless by this evil plant that gives mouth sores to cattle and displaces their food sources.

Back to (A), then:
So wait: in (A), it's the milky sap that gives the mouth sores to cattle -- not the leafy spurge itself, as (B) would indicate. In that sense, (B) seems to be a slightly better choice. It's a bigger problem, presumably, if the entire plant gives mouth sores to cattle.

More importantly: "displacing grasses and rendering rangeland useless", would generally modify the preceding clause. And that's pretty illogical in (A): "that gives mouth sores to cattle" has absolutely nothing to do with "displacing grasses." And in that sense, (B) is much clearer.

So (A) is gone. And the rest are easier to eliminate:

Parallelism in (C) is clearly wrong: "... and displacing grasses" is parallel to what, exactly? "Having milky sap", I guess? That's a mess. We can comfortably eliminate (C).

I really don't love "having been invaded" in this case. In general, "having + verb" needs to be the first of two actions, and that's just not happening here. (For more on this topic, see our last chat transcript.)

Also, the parallelism at the end of the sentence isn't ideal: "... with milky sap that gives mouth sores to cattle, displaces grasses..., and renders rangeland worthless." The sap displaces grasses? That doesn't make sense. (D) is gone.

(E) is similar to (D): "having been" doesn't seem quite right, and "giving mouth sores to cattle" is parallel to "displacing grasses", suggesting that the milky sap displaces grasses -- and that doesn't make sense. (E) is gone, too, and (B) is our winner.

--- The X marker (in yellow highlight) from a logical meaning obviously refers to the milky sap [Reason : herbaceous plant by itself cannot cause sores obviously. Per logic, it is the milky sap INSIDE the plant that is causing the sores]

Hi jabhatta2,

This is where I think you made a mistake. "a plant that gives mouth sores to cattle" is fine, so we really should not force the that to refer to milky sap. As for whether it should, we'd need additional information to take that call: is it the plant that's bad for cattle, or is it a particular type of milky sap that's bad for cattle? The best thing to do here is to avoid that call entirely.

Thanks so much AjiteshArun for responding.

It has to be the MILKY SAP that causes the sores

Poison Ivy for example causes irratation because if you rub Poison ivy, the oil from the Poison Ivy is the reason for the irritation.

Simirlarly, w/o having ANY real life knowledge of plants -- the herbaceous plant BY itself cannot cause sores. It has to be some chemical in the herbaceous plant (oil or in this case, MILKY SAP) that is causing the sores.

Just based on reasoning alone, sores are not caused by plants by itself. It has to be the MILKY SAP

GMATNinja egmat

In Option 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.

I am trying to break the sentence-

If "a herbaceous plant" is a modifier for "Leafy spurge"

And if

"from Eurasia with milky sap" is giving extra information for "a herbaceous plant"

and if

"that gives mouth sores to cattle" is providing extra information about "milky sap".

Then why can't

"displacing" and "rendering", modify "leafy spurge"?

V-ing modifier without comma?

Also as we know, that modifier can modify faraway noun/clause, if there is another modifier in between and if in between modifier can't take any other place.

Also In option 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.

Why, "that" can't modify "milky sap"?
Is it because of "comma" before "that"?

Also wouldn't it would sound a little illogical, that "a herbaceous plant gives mouth sore"?
Shouldn't it be "milky sap" as per the original meaning?

Hi GMATNinja MartyTargetTestPrep

Sorry about raking up an already discussed question. But I couldn't find a post that clarifies my doubt and hence this post.

"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."

In this given sentence, can't we consider "a herbaceous plant from Eurasia with milky sap that gives mouth sores to cattle" as a non-essential modifier and thereby having core as "About 5 million acres in the United States have been invaded by leafy spurge, displacing grasses and other cattle food and rendering rangeland worthless."

Now isn't "displacing grasses and other cattle food and rendering rangeland worthless." modifying the entire clause "About 5 million acres in the United States have been invaded by leafy spurge" ?

Not sure if I am right but the only problem I can identify in this is a comma before 'and rendering'. i.e. if the sentence had been "About 5 million acres in the United States have been invaded by leafy spurge, displacing grasses and other cattle food, and rendering rangeland worthless." couldn't it be right ?