Introductory and concluding prepositional phrase

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The confusion is with introductory prepositional phrases. Are they always act as a adverbial phrase or ,sometimes ,as adjectival phrases also?

( I think that the introductory prepositional phrases always act as Adverbial modifiers because they make the following main clause precise or add details to the following main clause).

what is your opinion?


kindly have a look on following examples..

1. after lunch, they swam for two hours in the pool.

here : after lunch is prepositional adverbial phrase modifying the action in the main clause. Hence it is correct. Is it?

2. They swam for two hours in the pool after lunch.

here it seems to be correct also.

3. They swam for two hours in the pool ,after lunch. A comma before the prepositional phrase.

Is it a correct sentence....or the meaning of this sentence is same as that of the first sentence?

Another example:

Opposition leader Viktor Yanukovych has clearly won, by a 3.48 percentage margin, Ukraine's presidential election held recently.

Here: prepositional phrase is set off by pair of commas .....why this is so?

( I think that the phrase is non essential phrase. Is it so?)

Also, what role does this prepositional phrase play --- adjectival or adverbial?

( I suppose that it plays an adverbial role as it answers the question "HOW"? )

Now let's see this eg....

By a 3.48 percentage margin,Opposition leader Viktor Yanukovych has clearly won Ukraine's presidential election held recently.

Here: does this prepositional phrase play the same role as in the preceding sentence?

(i think that it plays the same role as in the first sentence..)

Is it so?

Do Introductory prepositional phrases always set up the ground for the action in the main clause?
If yes, then they always act as adverbial phrase.



See another eg:

Like John, Ricky enjoys playing cricket.
But here : introductory prepositional phrase, like John, modifies the noun, Ricky.

hence it is adjectival phrase rather than a adverbial phrase. Is it so?

this , again , can be written as.....
Ricky , like john, enjoys playing cricket. Here " like John": is non essential phrase as it is set off with pair of commas.
Is it so?

Now let's see the concluding prepositional phrase..

Here ,prepositional phrase come after the comma in the main clause...

For eg: Eco efficiency has become a goal for companies worldwide, with many realizing significant cost savings from such innovations.

Why the prepositional phrase starts with a comma and what role does it play?

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by lunarpower » Sat Mar 06, 2010 6:19 pm
Rajat Khandelwal wrote:The confusion is with introductory prepositional phrases. Are they always act as a adverbial phrase or ,sometimes ,as adjectival phrases also?

(I think that the introductory prepositional phrases always act as Adverbial modifiers because they make the following main clause precise or add details to the following main clause).
yes, it's usually the case that introductory prepositional modifiers are adverbial.

there are a couple of cases in which it's difficult to make this call. for instance, in a typical "like" sentence --
like my brother, i have a strange sense of humor
-- it's not entirely clear whether one would classify this modifier as adverbial (modifying the idea of having a strange sense of humor) or adjectival (modifying "i"). fortunately, we don't ultimately care -- the gmat is not going to ask us for grammatical classifications.

i can also write sentences in which the opening prepositional modifier is unambiguously acting as an adjective. for example, here is one:
Of pure Blackfoot Indian heritage, jonas is eligible to receive free college scholarships from the tribal government.
in this sentence, the opening modifier is definitely adjectival ("of pure blackfoot indian heritage" clearly modifies jonas), but it's a bit of an awkward sentence. most similarly structured sentences that i can make up off the top of my head are also awkward.
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by lunarpower » Sat Mar 06, 2010 6:23 pm
kindly have a look on following examples..

1. after lunch, they swam for two hours in the pool.

here : after lunch is prepositional adverbial phrase modifying the action in the main clause. Hence it is correct. Is it?
this is fine, provided that there is an antecedent somewhere for "they".
2. They swam for two hours in the pool after lunch.

here it seems to be correct also.
this is fine, although the placement of the prepositional phrase is more confusing and less immediately readable.
note that such "awkward placement" will never be the only reason why an answer is incorrect, but is often placed in tandem with other errors.
3. They swam for two hours in the pool ,after lunch. A comma before the prepositional phrase.

Is it a correct sentence....or the meaning of this sentence is same as that of the first sentence?
you can't use commas in this sort of construction.

the only time i've ever seen a prepositional phrase AFTER a comma is when either
(1) the sentence is unreadable / confusing / ambiguous WITHOUT the comma (see your example about the Ukrainian election below), or
(2) that prepositional phrase is acting as an adjective to modify the proceeding noun.
for example:
Michael Beauregard, of Bay St. Louis, Mississippi, received a Purple Heart today for his courage in battle.
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by lunarpower » Sat Mar 06, 2010 6:30 pm
Another example:

Opposition leader Viktor Yanukovych has clearly won, by a 3.48 percentage margin, Ukraine's presidential election held recently.

Here: prepositional phrase is set off by pair of commas .....why this is so?
the commas don't distort the meaning in this case, and this sentence is absolutely unreadable without them. (try re-writing this sentence without the commas to see what i mean.)
( I think that the phrase is non essential phrase. Is it so?)
yes. (this is actually the definition of "nonessential modifier" -- a modifier that is set off by commas)
Also, what role does this prepositional phrase play --- adjectival or adverbial?

( I suppose that it plays an adverbial role as it answers the question "HOW"? )
yes.
Now let's see this eg....

By a 3.48 percentage margin,Opposition leader Viktor Yanukovych has clearly won Ukraine's presidential election held recently.

Here: does this prepositional phrase play the same role as in the preceding sentence?

(i think that it plays the same role as in the first sentence..)

Is it so?
that's probably fine, although it would be considered less awkward in this case if you switched "by" to "with".
(this is one of those extremely particular specifics that is well beyond the scope of the gmat: it's commonplace in english to say "they won by X points", but you'll NEVER see "by X points, they won").
Do Introductory prepositional phrases always set up the ground for the action in the main clause?
pretty much, yes. that's why they are placed at the beginning of the sentence.
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by lunarpower » Sat Mar 06, 2010 6:44 pm
See another eg:

Like John, Ricky enjoys playing cricket.
But here : introductory prepositional phrase, like John, modifies the noun, Ricky.

hence it is adjectival phrase rather than a adverbial phrase. Is it so?
as i stated above, i really don't think there's any point in analyzing such fine grammatical distinctions. if you understand the functioning of modifiers involving the word "like", that's all you need.

there is absolutely no benefit whatsoever in being able to classify the modifier as "adverbial" or "adjectival" or whatever else! the only thing that matters is that you understand how the modifier works.
this , again , can be written as.....
Ricky , like john, enjoys playing cricket. Here " like John": is non essential phrase as it is set off with pair of commas.
Is it so?
as i pointed out above, that's a somewhat problematic classification, and i don't really know (with any confidence) how you would classify it.
but, again, this is an ok sentence, and sentences that look like it are also ok. that's all you really need to know!
provided you understand that this sentence is ok, any further attempts at classification are a complete waste of time (at least as far as improving your gmat score is concerned).
For eg: Eco efficiency has become a goal for companies worldwide, with many realizing significant cost savings from such innovations.

Why the prepositional phrase starts with a comma and what role does it play?
where'd you get this sentence? it's certainly not official, as there are a couple of large problems with it.
i'd rather not analyze it, since it's poorly written and thus unreliable.
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by Rajat Khandelwal » Sat Mar 06, 2010 8:41 pm
Thank you Ron...
can also write sentences in which the opening prepositional modifier is unambiguously acting as an adjective. for example, here is one:
Of pure Blackfoot Indian heritage, jonas is eligible to receive free college scholarships from the tribal government.
in this sentence, the opening modifier is definitely adjectival ("of pure Blackfoot Indian heritage" clearly modifies Jonas), but it's a bit of an awkward sentence. most similarly structured sentences that i can make up off the top of my head are also awkward.
yes it is definitely true....here" Of pure Blackfoot Indian heritage" acts as complement ....Jonas is of pure Blackfoot Indian heritage..

you can't use commas in this sort of construction.

the only time i've ever seen a prepositional phrase AFTER a comma is when either
(1) the sentence is unreadable / confusing / ambiguous WITHOUT the comma (see your example about the Ukrainian election below), or
(2) that prepositional phrase is acting as an adjective to modify the proceeding noun.
for example:
Michael Beauregard, of Bay St. Louis, Mississippi, received a Purple Heart today for his courage in battle.
(1)Opposition leader Viktor Yanukovych has clearly won, by a 3.48 percentage margin, Ukraine's presidential election held recently.
If i rewrite the sentence without using comma...

Opposition leader Viktor Yanukovych has clearly won by a 3.48 percentage margin Ukraine's presidential election held recently.


Then it seems that "by a 3.48 percentage margin" acts as a direct object of the verb, won. Isn't?

Another sentence...

Hydrogen peroxide is more efficient at disinfecting bacteria than heavy water, by its foaming action caused by the release of nascent oxygen.

here the sentence can be written as..

Hydrogen peroxideby its foaming action caused by the release of nascent oxygen , is more efficient at disinfecting bacteria than heavy water.

Here the prepositional phrase set off with a pair of commas modifies Hydrogen peroxide. hence it acts as a adjectival modifier.Isn't?

Another way...

With its foaming action caused by the release of nascent oxygen , Hydrogen peroxide more efficient at disinfecting bacteria than heavy water.


but here it would modify the principal verb in the main clause ("is more efficient"). As it answers the question ,"HOW Hydrogen peroxide is more efficient "?

So, the prepositional phrase acts as a adverbial modifier. Isn't?

Which one is true here...adjectival or adverbial phrase?

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by lunarpower » Sat Mar 06, 2010 10:35 pm
Rajat Khandelwal wrote:Opposition leader Viktor Yanukovych has clearly won by a 3.48 percentage margin Ukraine's presidential election held recently.


Then it seems that "by a 3.48 percentage margin" acts as a direct object of the verb, won. Isn't?
no. big loud emphatic NO.
it's impossible for a prepositional phrase to be the direct object of a verb. the only eligible objects for verbs are nouns and pronouns.

there are two reasons to set this modifier off with commas:

(1) the sentence is absolutely unreadable without the commas. (in fact, it's so unreadable that you mistook a prepositional phrase for an object!)

(2) if you don't set off the percentage modifier with commas, the sentence actually becomes redundant -- in this case, there is no further need for the adverb "clearly". if the modifier is set off by commas, then this isn't considered redundant anymore -- it falls under the rubric of "emphasis".
here's another illustration of the same principle:
jonas is much taller than his brother by an entire foot --> redundant
jonas is much taller than his brother, by an entire foot --> emphatic; no longer redundant

--

it IS possible to place an essential (no commas) prepositional phrase between a verb and its object, but only when that essential modifier is extremely short.

for instance:
i dedicated a song to my father
i dedicated to my father a song that recounted all the lessons he taught me in life


both of these are correct constructions; if you reverse the placement in the second one, it becomes too confusing / difficult to read.
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by lunarpower » Sat Mar 06, 2010 10:45 pm
here the sentence can be written as..

Hydrogen peroxideby its foaming action caused by the release of nascent oxygen , is more efficient at disinfecting bacteria than heavy water.

Here the prepositional phrase set off with a pair of commas modifies Hydrogen peroxide. hence it acts as a adjectival modifier.Isn't?
that is such an awful sentence (see objections in first post) that i'm going to make up a better one, just so that has some sort of legitimate meaning of which to speak.

note that, if a modifier is in the middle of a sentence, you can never use only one comma to set it off.
either you use 2 commas (one on either side), or you use none.

i think you may have just left out the comma that precedes the modifier in the sentence, but, if not, make sure you know that it belongs there.

here's the analogy:
new world monkeys, with their prehensile tails, are able to swing through trees without occupying their hands.
vs.
with their prehensile tails, new world monkeys are able to swing through trees without occupying their hands.

these modifiers are best thought of as adverbial, because the sentence is considered incorrect if the modifier doesn't have that sort of relationship to the action in the main clause.
i.e., the prehensile tail is essential to the monkeys' ability to swing through the trees without using their hands, so it's appropriate to consider this modifier adverbial.

again, however, let me reiterate my previous statement: the formal classification here isn't what's important. what's important is that you have examples of correct and incorrect constructions at hand, so that you may judge whether a new example is correct or incorrect without having to resort to first principles every time.
a lot of students REALLY underestimate the importance of this. if you consciously apply grammatical rules to every construction that you see -- rather than observing patterns among correct and incorrect examples, and extrapolating based on those patterns -- you will almost certainly take too much time to deal with these problems.

with this consideration in mind, you should NOT spend too much effort into formal classification of these modifiers as adverbial or adjectival -- since, at the end of the day, all that really matters is "ok or not ok".
if you can remember "things that look like this are acceptable" and "things that look like that are unacceptable", then your time management will be much improved.
Last edited by lunarpower on Sat Mar 06, 2010 11:09 pm, edited 1 time in total.
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by Rajat Khandelwal » Sat Mar 06, 2010 10:49 pm
Another sentence...

Hydrogen peroxide is more efficient at disinfecting bacteria than heavy water, by its foaming action caused by the release of nascent oxygen.

here the sentence can be written as..

Hydrogen peroxide by its foaming action caused by the release of nascent oxygen , is more efficient at disinfecting bacteria than heavy water.

Here the prepositional phrase set off with a pair of commas modifies Hydrogen peroxide. hence it acts as a adjectival modifier.Isn't?

Another way...

With its foaming action caused by the release of nascent oxygen , Hydrogen peroxide more efficient at disinfecting bacteria than heavy water.


but here it would modify the principal verb in the main clause ("is more efficient"). As it answers the question ,"HOW Hydrogen peroxide is more efficient "?

So, the prepositional phrase acts as a adverbial modifier. Isn't?

Which one is true here...adjectival or adverbial phrase?

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by lunarpower » Sat Mar 06, 2010 11:08 pm
Rajat Khandelwal wrote:Another sentence...

Hydrogen peroxide is more efficient at disinfecting bacteria than heavy water, by its foaming action caused by the release of nascent oxygen.

here the sentence can be written as..

Hydrogen peroxide by its foaming action caused by the release of nascent oxygen , is more efficient at disinfecting bacteria than heavy water.

Here the prepositional phrase set off with a pair of commas modifies Hydrogen peroxide. hence it acts as a adjectival modifier.Isn't?

Another way...

With its foaming action caused by the release of nascent oxygen , Hydrogen peroxide more efficient at disinfecting bacteria than heavy water.


but here it would modify the principal verb in the main clause ("is more efficient"). As it answers the question ,"HOW Hydrogen peroxide is more efficient "?

So, the prepositional phrase acts as a adverbial modifier. Isn't?

Which one is true here...adjectival or adverbial phrase?
hmm? it appears you've just reproduced the lower half of your post. i already addressed all of these forms in the post directly above this latest one:
https://www.beatthegmat.com/introductory ... tml#234032

i changed the sentence to something that makes sense (see my objections above), and added a comma so that there really is "a pair of commas" where you say there's one, but i already responded to all of this. see my previous post.
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by lunarpower » Sun Mar 07, 2010 2:04 am
sorry, i just realized that there's another thread dealing with the hydrogen peroxide problem. i voiced my objections to that problem over on that page.

link:
https://www.beatthegmat.com/hydrogen-per ... tml#233981

my explanation on the linked page shows why i changed the example -- that's one of the worst sentences i've seen around here in a while.
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by Rajat Khandelwal » Sun Mar 07, 2010 9:44 am
thanks ...Ron
new world monkeys, with their prehensile tails, are able to swing through trees without occupying their hands.
vs.
with their prehensile tails, new world monkeys are able to swing through trees without occupying their hands.

these modifiers are best thought of as adverbial, because the sentence is considered incorrect if the modifier doesn't have that sort of relationship to the action in the main clause.
i.e., the prehensile tail is essential to the monkeys' ability to swing through the trees without using their hands, so it's appropriate to consider this modifier adverbial.
Do the two examples given above convey the same meaning as the following example....?( concluding prepositional phrase)

New world monkeys are able to swing through trees without occupying their hands,with their prehensile tails.

It is equivalent to my first example ...They swam for two hours in the pool ,after lunch. A comma before the concluding prepositional phrase. Hence , i think it is wrong saying this . Isn't?

Also, I think that it is a case of misplaced modifier . It seems to modify "hands" . Or Does it still act as an adverbial phrase ?

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by lunarpower » Mon Mar 08, 2010 4:28 am
Rajat Khandelwal wrote:Do the two examples given above convey the same meaning as the following example....?( concluding prepositional phrase)

New world monkeys are able to swing through trees without occupying their hands,with their prehensile tails.

It is equivalent to my first example ...They swam for two hours in the pool ,after lunch. A comma before the concluding prepositional phrase. Hence , i think it is wrong saying this . Isn't?

Also, I think that it is a case of misplaced modifier . It seems to modify "hands" . Or Does it still act as an adverbial phrase ?
nah, it's still an adverbial phrase. but adverbial phrases don't have complete freedom of placement; they still need to be placed as close as possible to the clause that they modify.
in this case, that clause is "new world monkeys are able to swing through trees", so your adverbial modifier must be placed in proximity to this clause.
this means one of two places -- either set off with a comma before the clause ("With their prehensile tails, new world monkeys...") or set off with two commas within the clause ("New world monkeys, with their prehensile tails, ...")
if you didn't have the other modifier ("without occupying their hands"), then you could also place this modifier at the end of the sentence, without a comma. however, you wouldn't want to do that with the current version of the sentence, since the clash between the two modifiers would render the sentence essentially unreadable.

if you want this sentence to create a better analogy to "they swam in the pool for two hours after lunch", then you should strike the modifier "without occupying their hands".
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by Rajat Khandelwal » Mon Mar 08, 2010 6:41 am
Thank you Ron

But i keep troubling you..

:)

New world monkeys with their prehensile tails are able to swing through trees without occupying their hands.

Here Does " with their prehensile tails" when used without comma modify New world Monkeys or still an adverbial phrase.

(As it makes the monkeys precise ,thus acting as an adjectival phrase .....but also it answers the question HOW, thereby acting as an adverbial phrase? )

And what does the role "without occupying their hands" play in the sentence ?

The same reasoning can be applied to here also.., i think..Isn't?

I think it also acts as an adverbial phrase. Isn't?

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by lunarpower » Wed Mar 10, 2010 4:50 am
Rajat Khandelwal wrote:Thank you Ron

But i keep troubling you..

:)

New world monkeys with their prehensile tails are able to swing through trees without occupying their hands.
nah. in that case, it's adjectival, modifying "monkeys". also, it doesn't make sense to use "their", for reasons below this line.

if you have "NOUN + no comma + prep ph", and the noun is the subject of the sentence, then that prepositional phrase should pretty much always be adjectival (modifying the subject).

****** WARNING: EVERYTHING UNDER THIS LINE IS PROBABLY TOO ADVANCED / NUANCED TO MAKE ANY DIFFERENCE ON THE EXAM ******

since there are no commas, that's an essential modifier -- meaning it's necessary to the meaning of the sentence.
since all new world monkeys have prehensile tails, this doesn't make sense. i.e., you only use an essential modifier when you're actually narrowing the possibilities for something.
i.e.
"new world monkeys with prehensile tails" --> refers only to the ones that actually have prehensile tails (assuming that at least some of them don't have such tails"

when you have "with their...", this actually implies that the monkeys have tails that they could be either carrying or not carrying, and that you are only referring to the monkeys that are actually carrying their tails at the time.
i have no formal explanation for this -- it's just the way the language is used.
e.g.
men with families were offended by the joke --> all men with families were offended, whether their families were present or not.
men with their families were offended by the joke --> only the men whose families were actually present were offended by the joke.

same deal here, although it leads to a sentence that makes little sense.
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