Horses have a unique system of interlocking ligaments and bones

The original answer choice has a verb-ing after the comma. This means that it should modify the preceding clause. In the context of the sentence this is incorrect as serving cannot modify Horses - which is the subject of the first clause.

B and C are out because of the usage of serve.
We need serves as unique system (singular) needs - serves (singular)

out of D and E , E is the best as D again contains incorrect usage of which as well as incorrect usage of verb-ing

As an addendum, may I say that A is a run-on, which will be clear when you mask the back to back modifiers and D is a fragment without a verb for the subordinate clause started by ‘in which’. (in which effectively means ‘which’)

That refers to the immediately preceeding noun and "legs" is the immediately preceeding noun in this case. Then why the use of serves is correct????
Please clarify

Horses have a unique system of interlocking ligaments and bones in their legs that ...

"that" doesn't refer to their legs but refer to "a unique system of interlocking ligaments and bones". I think you are confused about "which"

Horses have a unique system of interlocking ligaments and bones in their legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is they are able to sleep standing up.
a) legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is
b) legs that serve as a kind of sling in which to suspend their body weight, the muscles in their limbs being completely relaxed; as a result,
c) legs that serve as a kind of sling in which, with their body weight suspended while the muscles in their limbs are completely relaxed, the result is
d) legs that serves as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, having the result that
e) legs that serves as a kind of sling in which their body weight is suspended while the muscles in their limbs are completely relaxed; as a result,

1.legs are not serving;the serving is wrongly modifying the legs.
2.B,C and D are incorrect meaning and illogical.
3.Option E is the correct answer.

Hi kparik86, that is not correct:).

Here is a significant flexibility that that has, in terms of what it modifies. For example, in the following official question:

Marconi conceived of the radio as a tool for private conversation that could substitute for the telephone; instead, it has become precisely the opposite, a tool for communicating with a large, public audience.

that is clearly modifying tool (and not private conversation).

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

Horses have a unique system of interlocking ligaments and bones in their legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is they are able to sleep standing up.

a) legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is
- incorrect. "the result is they are able to sleep standing up" is completely awkward. i'd even say unidiomatic. should be: "AS A RESULT..."

b) legs that serve as a kind of sling in which to suspend their body weight, the muscles in their limbs being completely relaxed; as a result,
- "being" awkwardly placed in the middle of a sentence...out

c) legs that serve as a kind of sling in which, with their body weight suspended while the muscles in their limbs are completely relaxed, the result is
- "serve" should be "serves"...this is an issue present in "A" & "B" too. What "serves"? The SYSTEM (of interlocking ligaments). The system SERVES.

d) legs that serves as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, having the result that
- "having the result" = awkward, definitely incorrect

e) legs that serves as a kind of sling in which their body weight is suspended while the muscles in their limbs are completely relaxed; as a result,
- correct

Not too bad of a question. If you see the "serve" vs. "serves" split quickly, you should have a 50/50 between "D" & "E" and between the 2, very easy to eliminate "D". If done well, should take no longer than a minute.

Hi pairakesh10,

Thank you for your question. Let's tackle this question one problem at a time. After looking over the possible answers, a few differences jumped out that we can address:

1. serve vs. serves
2. ending with semicolons vs. commas
3. comma placement in the rest of the answer

Let's start with #1: serve vs. serves. Since the verb is referring to the singular "a unique system," the verb needs to be the singular "serves." Therefore, let's rule out answers B & C because they use the plural "serve."

Next, let's look at #2 on the list: ending with a semicolon vs. a comma. We need to make sure whatever comes after the word "relaxed" is punctuated properly. If it's an independent clause, it needs a semicolon. If it's a dependent clause, it needs a comma or no punctuation. Let's see if they work:

a) legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is they are able to sleep standing up.

This is an independent clause, which means it could stand alone as its own sentence. Independent clauses need to be separated by semicolons - a comma isn't good enough and will create a comma splice. Therefore, this answer is INCORRECT because of faulty punctuation.

d) legs that serves as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, having the result that they are able to sleep standing up.

This answer is INCORRECT because it doesn't make sense how it's punctuated. By putting the phrase I crossed out above between commas, it is now a non-essential phrase. If we take it out, the rest of the sentence doesn't make sense. Therefore, the commas are in the wrong places for this to work, making it wrong.

e) legs that serves as a kind of sling in which their body weight is suspended while the muscles in their limbs are completely relaxed; as a result, they are able to sleep standing up.

This is the CORRECT answer because it uses a semicolon after "relaxed" to show that everything after it is part of an independent clause.

After looking at subject-verb agreement and punctuation, it's clear that E is the CORRECT answer!

Horses have a unique system of interlocking ligaments and bones in their legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is they are able to sleep standing up.

Yes System is the subject. Here's how you can logically tell its the subject:
A,B, and C, say that 'in' (i.e. in which) the Legs or the ligaments and bones (two plausible subjects despite the restrictive modifier) are what serve as a sling. Instead, it should be the system, in which ligaments, bones or legs serve as a swing.

The swing can be inside the system but not inside the legs/bones/ligaments.

I want to say about order of steps of solving the sc problem. this is for non native like me.

1. find the global errors first
global errors can be structure error, most easy error , or meaning error.

2. find grammatical minor error or hard meaning error when there are 2 remaining choices.

a. grammatical minor error is easy to explain but hard to find out. this error is agreement or plural/singular error. this error can be fatal because at first we focus our mind on global error and we continue focus our mind on global error and forget minor error.

b. hard meaning error.
when a choice has meaning error but hard to realize if we read only the choice. the error is more easy if we read 2 choice and compare them.

apply this order to our problem.

we can eliminate choice A , C and D first. these choices contain global error.
between choice B and E, there is mechanical minor errors. we compare and we see agreement error.

Horses have a unique system of interlocking ligaments and bones in their legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is they are able to sleep standing up.

How to solve this Question in one minute ..
For any question which involves modifiers, we can dumb the modifier and connect the sentences to know if the sentence is still logical. Modifiers bring much much quality to the complete sentence but by removing modifiers the sentence should still make sense.
(A) legs, serving as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, the result is
Let's dumb modifier and check the sentence.
Horses have a unique system of interlocking ligaments and bones in their legs,serving as a kind of sling in which the result is they are able to sleep standing up. Meaningless. Dumb A

(B) legs that serve as a kind of sling in which to suspend their body weight, the muscles in their limbs being completely relaxed; as a result,
Being completely . No verb here.

(C) legs that serve as a kind of sling in which, with their body weight suspended while the muscles in their limbs are completely relaxed, the result is
legs that serve as a kind of sling in which the result is ..Completely meaningless

(D) legs that serves as a kind of sling in which, with their body weight suspended and the muscles in their limbs completely relaxed, having the result that
legs that serves as a kind of sling in which having the result that. No meaning

(E) legs that serves as a kind of sling in which their body weight is suspended while the muscles in their limbs are completely relaxed; as a result,
Clear and comfort. E should be the best choice

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