Since the teacher introduced the classroom reward system, students hav

The question test your knowledge on parallel lists..... There are two parallel lists in the question "students X a,b, and c, and Y" - have begun and have stopped is one list joined by ",and" / paying closer attention, completing homework, and following directions is another list joined by ",and"

A) following directions, and have stopped causing - Incorrect, Doesn't have "and" for the second list

B) to follow directions, and have stopped causing - Incorrect, Second list is not parallel

C) and following directions, having stopped causing - Incorrect, Doesn't have "and" for the First list + Having is wrong

D) and following directions, and have stopped causing - Correct

E) following directions, and have caused - Incorrect, Doesn't have "and" for the second list + and caused is wrong

Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework, following directions, and have stopped causing disruptions during lessons.

Structure: Since the teacher introduced the program, students have begun X(a,b, and c), and have stopped Y. This is the structure we need to communicate the intended meaning.

Note: Stopping causing disruption sounds nonsensical and can't be parallel to the previous list as it denotes the other result which took place because of the introduction of the program.

Option D corrects this structure issue and conveys intended meaning.

IMHO D

Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework, following directions, and have stopped causing disruptions during lessons.

A) following directions, and have stopped causing - wrong parallelism

B) to follow directions, and have stopped causing - wrong parallelism

C) and following directions, having stopped causing - wrong construction

D) and following directions, and have stopped causing- correct parallelism

E) following directions, and have caused wrong meaning

IMO Correct answer is D

Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework, following directions, and have stopped causing disruptions during lessons.

A) following directions, and have stopped causing - 2 "AND"s as parallelism markers need to have same structure of items both before and after list; Missing an AND before "...following directions", breaks parallelism

B) to follow directions, and have stopped causing - to +Verb breaks parallelism

C) and following directions, having stopped causing - "having stopped causing" is not parallel with "have begun paying" in the non-underlined portion of the sentence.

D) and following directions, and have stopped causing - Correct

E) following directions, and have caused - Changes the meaning of the sentence.

I have posted the official explanation HERE

Meaning: after T intro a system, two things happened: [1] a list, and [2] is a clause;
(A) "[1] have begun {playg…compg…folwg…}, and [2] have {stopped…}" this implies the last element of the [1] list is "have stopped", actually, the last element of the list is "folwg" (which should be preceded by "and"), out;
(B) "to follow" breaks list parallelism, out;
(C) "having stopped…" is treating the [2] part as a part mod, unintended;
(E) same prob as (A), with parallelism issue;

Answer (D).

Hi generis,

I have small doubt regarding the explanation posted.

As per the GMAT "Comma + and" Joins two independent clauses (FANBOYS Rul"e).
In the above Sentence There is no Independent clause after "Comma + and". The clause after Comma + And don't have a subject of its own.

Could you please help me with this

The explanation, of what is the correct answer and why, has been beaten to death by experts and those who have got it correct on the first go.

I, however, didn't get it correct the first time around. Therefore I will hereby address my clones and others who think like me (at least did so this time).

I couldn't get for the love of God why this would be the right answer. I made the mistake of being casual; I skimmed through it, saw two ('redundant') ands back to back, thought I was very smart to have caught "the mistake" in this easily. But here's why I was wrong.

Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework and following directions, and have stopped causing disruptions during lessons.

This above is the correct answer. I'll break it down, tear it to shreds to explain different how multiple independent clauses (or we can say sentences) have been jammed in this to make gem of a sentence.

1. Since the teacher introduced the classroom reward system, students have begun paying closer attention
2. Since the teacher introduced the classroom reward system, students have begun completing homework
3. Since the teacher introduced the classroom reward system, students have begun following directions.
4. Since the teacher introduced the classroom reward system, students have stopped causing disruptions during lessons.

Now, in order to form one sweet sentence out of this mess, let's group like verb forms :

1. Present Participle:
• paying
• completing
• following
• causing

Now we can club them together in logical, parallel lists, omit repeating words. We get this:

1. Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework and following directions.

2. Since the teacher introduced the classroom reward system, students have stopped causing disruptions during lessons.

The second type of verb forms in the original sentence is:

2. Past Participles:
•(have) begun
•(have) stopped

Now let's rewrite this sentence stringing the like verbs together, in parallel:

Since the teacher introduced the classroom reward system, students have begun paying closer attention, completing homework and following directions, and have stopped causing disruptions during lessons.

We now see clearly, that there are two parallelisms at play here, one between verbs and the other among verb forms.

Posted from my mobile device

vishumangal , the verb have stopped does have a subject: students. We need an unusual comma before the second verb because the list in the first verb phrase could be confusing.

This sentence has only one independent clause. One subject (students) is followed by two verbs (have begun and have stopped). Usually we would not put a comma between students and the second verb.

In this case, we can insert an "extra" comma if doing so clarifies the sentence.

A comma does clarify this sentence: the comma signals to the reader that we are "leaving" the list structure [in verb phrase #1] and re-entering verb territory.
The verbs are perfectly parallel. If the first verb phrase contains many commas, we can use another comma to highlight the beginning of the second verb phrase.

This sentence "splits the verb." The 3- or 4 word verbs are split into an anchor (have begun, have stopped) and their respective verb endings (__ ING participle phrases).

The verb split and the list create two "levels":
1) the first part of the split (have begun, have stopped) constitutes the Higher Level.
and
2) the second part of the split verb phrase (paying attention, etc.) is a list in one verb phrase, not a list in the other verb phrase, and constitutes the Lower Level. Below, "farther to the right" = lower level

Students
---HAVE BEGUN
------paying closer attention,
------completing homework,
------and
------following directions,
---AND
---HAVE STOPPED
------causing disruptions

When we reach the second part of the compound predicate, we may wonder, why is there another comma + and?

In order to show the reader (1) that the second and plus what follows it is separate from the list, and (2) that we are moving back "up" a level to the second verb, we add a comma.

This kind of clarifying comma does not actually sever the verb from the sentence.

Hope that helps.

Posted from my mobile device

wizardofoddz


Thanks for making me laugh. Much needed, much appreciated. Good snark. That's a hell of a username.
And this is a hell of a good answer. Kudos for the levity and the analysis.

(But "beaten to death by experts"? Wow. Who knew? I am an executioner of sentences now? And here I thought all this time that I was a writer and editor of sentences -- and occasionally an explicator of SC Sentences.)

Nicely done.

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