I am somewhat unclear regarding the use of “Based on” as a modifier in sentence.
Is this sentence correct.
Based on recent study,the scientists came to conclusion …
That should be
“Based on a recent study, the scientists came to the conclusion…”
or
“Based on recent studies, the scientists came to the conclusion…”
but otherwise it is correct.
You have used the modifier appropriately. 
Then why is this sentence incorrect
Based on the recent decline in enrollment,the admissions office decided to reevaluate its recruitment strategies.
this is an example taken from manhattan gmat’s sentence correction guide.
It looks correct to me (apart from the lack of a space after the comma, which I presume is a typo).
What does the guide have to say about it?
But in the guide they have corrected it using Because of … instead of Based on
Ahhh, okay…
It’s a very fine grammatical point which slipped by me on first reading.
Noun modifiers must be placed next to the nouns they modify. Verb or clause modifiers do not have the same requirement.
What was “based on” or “because of” the decline in enrollment? Not the admissions office itself, but the decision that was made. So you need to modify the verb ‘decided’, not the noun ‘office’.
“Based on” is a phrase with a past participle. Past participles are noun modifiers, because they describe the condition of a noun. For example, here, “based on the recent decline in enrollment” begs the question, “What was based on the recent decline?” Because the answer is a noun, this phrase is a noun modifier.
If you wanted to use “based on,” you could rewrite the sentence this way:
“Based on the recent decline in enrollment, the recruitment strategies were reevaluated by the admissions office.”
So the initial examples should have been:
'Based on a recent study, the conclusion of the scientists …"
I’m sure most native speakers would let that pass by without a second thought (as I did when I was focusing on the pluralisation of ‘studies’). It’s an example of how learners are expected to be better users of the language than first language users :-/
In the sentence
“Based on the recent decline in enrollment,the admissions office decided to reevaluate its recruitment strategies”, isnt it the decision which is based on recent decline in enrollment.
Can we rewrite it as
Based on the recent decline in enrollment,the decision to reevaluate the recruitment strategies was taken by the admissions office.
Do we have some rule for correcting such sentences .
Yes, you can.
As for a rule, I’m not sure if there is a hard and fast one, I’ll have to defer to someone else.
Hello Ricka343,
Basically, native speakers of English often use an introductory phrase beginning with ‘based on’ in a way that is technically grammatically incorrect, and it is generally recommended that this ‘misuse’ be avoided in formal writing.
The sentence above would not actually be unusual as far as everyday usage goes. People will understand that the sentence is telling us what the admission office’s decision was based on.
As has already been mentioned, this introductory participial phrase should modify the subject of the sentence. That is the technically correct way to use the phrase. Since the word ‘decision’ is not the subject of the sentence, the sentence is technically ‘wrong’.
However, there may actually be some who would argue that that is overly prescriptive. In my opinion, the way the ‘based on’ phrase was used in the quoted sentence is so very common that such a usage may eventually become formally acceptable. There are already a number of danglers that are considered by some to be ‘acceptable dangling modifiers’. For example, one website provides these as examples of acceptable danglers:
- Assuming it doesn’t rain, the garden tour begins at 3 p.m.
- Taking into account the rising cost of fuel, the price increase of retail goods is understandable.
These acceptable danglers have become acceptable through common usage, and I suspect that the sort of usage of ‘based on’ illustrated in your sentence will eventually come to be grudgingly accepted – perhaps even by hardcore prescriptivists.
Here is another thread that deals with the idea of dangling modifiers:
english-test.net/forum/ftopic13648.html
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[size=75]“It was an instinct to put the world in order that powered her mending split infinitives and snipping off dangling participles, smoothing away the knots and bumps until the prose before her took on a sheen, like perfect caramel.” ~ David leavitt[/size]