Use of Comma

Question

Hi All there...

I know this post is redundant but i need some clarity on when to use comma in-front of AND.

Below is an example sentence one with comma before AND & one without comma.

1) Since the last election, the lobbying effort initiated by environmental organizations, homeowners  , and  small business owners  has increased awareness of pending environmental legislation.

2) Since the last election, the lobbying effort initiated by environmental organizations, homeowners   and   small business owners  has increased awareness of pending environmental legislation.

Please explain the meaning of both the sentence.

For record 1) sentence is the actual Correct GMAT adherent sentence.

s8kadian · Accepted Answer

1. Use a comma before any coordinating conjunction (and, but, for, or, nor, so, yet) that links two independent clauses. 
 Example: "I went running, and I saw a duck."

2. Use a comma after a dependent clause that starts a sentence. 
 Example: "When I went running, I saw a duck."
 
 3. Use commas to offset appositives from the rest of the sentence.

Appositives act as synonyms for a juxtaposed word or phrase. For example, "While running, I saw a mallard, a kind of duck." "A kind of duck" is the appositive, which gives more information about "a mallard."

If the appositive occurs in the middle of the sentence, both sides of the phrase need a comma. As in, "A mallard, a kind of duck, attacked me."

Don't let the length of an appositive scare you. As long as the phrase somehow gives more information about its predecessor, you usually need a comma.

"A mallard, the kind of duck I saw when I went running, attacked me."

There's one exception to this rule. Don't offset a phrase that gives necessary information to the sentence. Usually, commas surround a non-essential clause or phrase. For example, "The duck that attacked me scared my friend" doesn't require any commas. Even though the phrase "that attacked me" describes "the duck," it provides essential information to the sentence. Otherwise, no one would know why the duck scared your friend. Clauses that begin with "that" are usually essential to the sentence and do not require commas.

4. Use commas to separate items in a series. 
 Example, "I saw a duck, a magician, and a liquor store when I went running."
 
 5. Use a comma after introductory adverbs. 
 Example : "Finally, I went running."  
 Example : "Unsurprisingly, I saw a duck when I went running."

6. Use a comma when the first word of the sentence is "yes" or "no." 
 Example :"Yes, I saw a duck when I went running." 
 Example :"No, the duck didn't bite me."

7. Use a comma when directly addressing someone or something in a sentence. 
 Example : My editor often asks, "Christina, is that article up yet?"

8. Use a comma between two adjectives that modify the same noun. 
 Example : "I saw the big, mean duck when I went running."

9. Use a comma to offset negation in a sentence. 
 Example : "I saw a duck, not a baby seal, when I went running."

mmagyar · Answer

The comma before the AND in a list of 3 or more items is permissive. That means you may choose to use it, or you may choose to omit it. It tends to be included in non-journalistic writing, but it is commonly omitted in newspapers and magazines. I believe this to be a result of the cost of printing an extra character millions of times.

In deciding to use or not use such a comma, you should consider the meaning.

1.) The main issue with using the comma occurs when we have a sentence structure like this:

I like  ,  , and  .
I like Joe, my brother, and Steve.

In this case, it looks like three items are in a list. However, there are actually only two items with a modifier. This becomes ambiguous. Is Joe being renamed by "my brother" (meaning they are the same thing), or is Joe a different person from my brother? How many people do I like?

This is fixed by omitting the comma before AND:

I like Joe, my brother and Steve.

Now, it is clear that Joe is not my brother, since the only potential modifier here is "my brother and Steve," and it is impossible for Joe to be renamed as both "my brother" and "Steve."

2.) On the other hand, omitting the comma can result in ambiguity. Consider the following example:

I like  ,  .
I like my parents, Joe and Lisa.

In this case, are my parents being renamed by "Joe and Lisa," or are Joe and Lisa separate from my parents? How many people do I like?

This ambiguity would be fixed by adding the comma:

I like my parents, Joe, and Lisa.

Now, it is clear that my parents are separate from Joe and Lisa, since "Joe" cannot rename my parents.

Conclusion: In deciding whether or not to include the comma before the AND in a 3+ item list, consider the meaning and pick the outcome with the least ambiguity. If neither way is ambiguous, then it doesn't matter whether you include the comma or not (unless you work for a company that has a preference, such as a newspaper company).

AmrithS · Answer

Dear Prakash,

It is good practice to put a comma before the FINAL conjunction that comes in a list. In the above sentence, even if the comma before 'and' is omitted, it wouldn't make much of a difference because the list is simple. 
Now, let me make things a little more complex:

Since the last election, the lobbying effort initiated by  environmental organizations and the red cross ,  homeowners and soccer-moms   , and   small business owners has increased awareness of pending environmental legislation.

In such a situation, adding a comma before the FINAL conjunction would make the list easier to read and comprehend.

I hope this clears your doubt.

Regards,

Entwistle

santivilla · Answer

@prakash111687 
Memorize this!
When listing more two items, always use a comma in-front of AND. By doing this, the sentence becomes clear and avoids the occurence of run-on sentences.
Cheers!

thevenus · Answer

Meaning wise, both the statements are same. 
 AND is used to separate more than two items in the list before the last item.

eg: Jack is a good linguist he can read,write and speak three languages.

OR

Jack is a good linguist he can read,write, and speak three languages.

Meanwhile,

(i) We should use a comma before AND in enlisting long items,such as

The countrymen were leading the army to the near forest to find the alien which was recently seen by the farmers,search every corner of the small mountains not to leave any space un-discovered,and to win the reward of 5000 gold coins.

(ii) When the last item can stand alone in the sentence OR has a slightly different intended//not very much relevant in meaning than the last items

eg: Monetary policies made by the Govt is very well appreciated by the normal public,businessmen,and the policy will benefit the NRIs who are willing to invest in India.

AND can be used with a comma or without a comma without changing the meaning of the sentence.
When a comma is put before the last item of the list it gives more clarity by separation of various items in the lists.

Hope this works !

Mahmud6 · Answer

Can  , and  be used for two items such as X, and Y? 
Is the following sentence correct?
Since the last election, the lobbying effort initiated by environmental organizations and the red cross , and  homeowners has increased awareness of pending environmental legislation.

s8kadian · Answer

Whether or not you put a comma before and depends on how you’re using and.

For e.g. when you list your dog’s qualities, you have to use a comma after each quality you list except the one that comes immediately before and. That comma is optional.

Correct  : The dog is young, well trained, and good natured.
 Correct  : The dog is young, well trained and good natured.

By the way, this rule only applies to lists of three or more items. You should not use a comma before and if you’re only mentioning two qualities.

Incorrect  : The dog is well trained, and good natured.
 Correct  : The dog is well trained and good natured.

This is true for proper names, ordinary nouns, verbs, or anything else.

Incorrect  : Sam, and Sarah take excellent care of their pets.
 Correct  : Sam and Sarah take excellent care of their pets.

Incorrect  : The dog barks, and plays.
 Correct  : The dog barks and plays.

Comma Before And That Joins Two Independent Clauses
 
The word and is a conjunction, and when a conjunction joins two independent clauses, you should use a comma with it. The proper place for the comma is before the conjunction.

On Monday we’ll see the Eiffel Tower , and  on Tuesday we’ll visit the Louvre. 
The sentence above contains two independent clauses , so it requires a comma before and. 
 
another example :

Correct  : It’s cold outside, and I can’t find my coat.

Incorrect  : Sam tossed the ball, and watched the dog chase it.
The first clause, Sam tossed the ball could stand on its own as a complete sentence, which means it’s an independent clause. But the second clause, watched the dog chase it, can’t stand by itself as a complete sentence. That means it’s a dependent clause, so we should not use a comma before and.

Correct  : Sam tossed the ball and watched the dog chase it.

Shrattitude · Answer

Is the use of "comma + And" in this sentence correct? It seems like an independent sentence with "his father" as the subject.

Financially unsupported by his doubting family, the young artist ultimately earned its approval and enjoyed some success when he pursued work modeling for fellow artists and photographers , and  photos of him graced the pages of a periodical his father read regularly.

VerbalBot · Answer

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Use of Comma

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Use of Comma

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