Editing Encyclopedia:Manual of Style (section)

===Commas===
{{Shortcut|MOS:COMMA|MOS:,}}

<ul><!--Do not convert this to a wikimarkup list; that approach cannot handle embedded tables.-->
<li>
A pair of [[comma]]s can bracket an [[Apposition|appositive]], [[relative clause]], or [[parenthesis (rhetoric)|parenthetical phrase]] (as can brackets or dashes, though with greater interruption of the sentence). For example:

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|John Smith, Janet Cooper's son, is a well-known playwright.}}
|-
| {{em|Correct:}}
| {{xt|Janet Cooper's son John Smith is a well-known playwright.}} (when Janet has multiple sons)
|-
| {{em|Correct:}}
| {{xt|Janet Cooper's son, John Smith, is a well-known playwright.}} (when Janet has only one son)
|}
Always use a ''pair'' of commas for this, unless another punctuation mark takes the place of the second comma:
{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Incorrect:}}
| {{!xt|The newest member, John Smith was blunt.}}<!-- There's actually a way to parse this such that it would be acceptable in some styles, but WP articles don't use such styles. -->
|-
| {{em|Correct:}}
| {{xt|Blunt comments came from the newest member, John Smith.}}
|-
| {{em|Correct:}}
| {{xt|The newest member, John Smith{{snd}}a retired teacher{{snd}}was blunt.}}
|}
</li>

<li>
Don't let other punctuation distract you from the need for a comma, especially when the comma collides with a bracket or parenthesis:

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|Burke and Wills, fed by locals (on beans, fish, and ''ngardu''), survived for a few months.}}
|-
| {{em|Incorrect:}}
| {{!xt|Burke and Wills, fed by locals (on beans, fish, and ''ngardu'') survived for a few months.}}
|}
</li>

<li>{{anchor|fewer commas}}
Modern{{efn|name=recent}} writing uses fewer commas; there are usually ways to simplify a sentence so that fewer are needed.

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Clear}}:
| {{xt|Schubert's heroes included Mozart, Beethoven, and Joseph and Michael Haydn.}}
|-
| {{em|Awkward}}:
| {{!xt|Mozart was, along with the Haydns, both Joseph and Michael, and also Beethoven, one of Schubert's heroes.}}
|}
</li>

{{Shortcut|MOS:GEOCOMMA}}
<li>{{anchor|Geographical references}}
In geographical references that include multiple levels of subordinate divisions (e.g., city, state/province, country), a comma separates each element and follows the last element unless followed by terminal punctuation or a closing parenthesis. The last element is treated as [[Wikipedia:Basic copyediting#Parenthetical comma|parenthetical]].

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|He traveled through North Carolina before staying in Chattanooga, Tennessee, for the night.}}<!-- About a 10-hour drive if he started in Virginia Beach and passed through Winston-Salem. -->
|-
| {{em|Incorrect:}}
| {{!xt|He traveled through North Carolina before staying in Chattanooga, Tennessee for the night.}}
|}

Also include commas when the geographical element is used as a disambiguator:

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|Hantratty received a PhD from the University of California, Irvine, in 1977.}}
|-
| {{em|Incorrect:}}
| {{!xt|Hantratty received a PhD from the University of California, Irvine in 1977.}}
|}
</li>

{{shortcut|MOS:DATECOMMA|MOS:YEARCOMMA}}
<li>{{anchor|Date commas}}
[[Wikipedia:Manual of Style/Dates and numbers#Dates, months, and years|Dates]] in month–day–year format require a comma after the day, as well as after the year, unless followed by other punctuation. The last element is treated as [[Wikipedia:Basic copyediting#Parenthetical comma|parenthetical]].

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|He set October 1, 2011, as the deadline for Patterson to meet his demands.}}
|-
| {{em|Incorrect:}}
| {{!xt|He set October 1, 2011 as the deadline for Patterson to meet his demands.}}
|}
</li>

{{shortcut|MOS:QUOTECOMMA}}
<li>{{anchor|Quotation commas}}
Place quotation marks by following {{Section link||Punctuation inside or outside}}. This is known as "logical quotation".

{| role="presentation" style="background:transparent;color: var( --color-base );"
|-
| {{em|Correct:}}
| {{xt|She said, "The weather changes too often", and made other complaints.}}
|-
| {{em|Incorrect:}}
| {{!xt|She said, "The weather changes too often," and made other complaints.}}
|}
</li>

<li>
A comma may be included before a quotation embedded within a sentence {{crossref|pw=y|(see {{section link||Quotation marks}})}}.
</li>

</ul>

====Serial commas<span class="anchor" id="Serial comma"></span><span class="anchor" id="Oxford comma"></span><span class="anchor" id="Oxford commas"></span><span class="anchor" id="Harvard comma"></span><span class="anchor" id="Harvard commas"></span>====
{{Shortcut|WP:OCOMMA|MOS:SERIAL|MOS:OXFORD|MOS:HARVARD}}
{{Redirect|MOS:OXFORD|Oxford spelling|Wikipedia:Manual of Style/Spelling#British English with "-ize" (Oxford spelling)}}

A [[serial comma]] (sometimes also known as an ''Oxford comma'' or ''Harvard comma'') is a comma used immediately before a conjunction (''and'', ''or'', ''nor'') in a list of three or more items.

{{Block indent|{{xt|ham, chips, and eggs}}{{spnd}}serial comma}}
{{Block indent|{{xt|ham, chips and eggs}}{{spnd}}no serial comma}}

Editors may use either convention so long as each article is internally consistent. Serial commas are more helpful when article text is complex, such as a list with multi-word items (especially if one contains its own "''and''"{{--)}} or a series of probably unfamiliar terms.

However, there are cases in which either omitting or including the serial comma results in ambiguity:

{{Block indent|{{!xt|The author thanked her friends, Sinéad O'Connor and Bob Marley}}{{spnd}}which may list either four or more people (the friends and the two people named) or two people (O'Connor and Marley, who are the friends).}}

{{Block indent|{{!xt|The author thanked a friend, Sinéad O'Connor, and Bob Marley}}{{spnd}}which may list either two people (O'Connor, who is the friend, and Marley) or three people (the first being the friend, the second O'Connor, and the third Marley).}}

In such cases of ambiguity, clarify one of four ways:
*Add or remove the serial comma.
*Use separate sentences, bullet lists, or some other structural change to clarify.
*Recast the sentence ("friends" case):
**To list two people: {{xt|The author thanked her friends Sinéad O'Connor and Bob Marley.}}
***Clearer: {{xt|The author thanked two friends – Sinéad O'Connor and Bob Marley.}}
**To list several people:
**: {{xt|The author thanked Sinéad O'Connor, Bob Marley and her friends}} or
**: {{xt|The author thanked Sinéad O'Connor, Bob Marley, and her friends}}.
***But not: {{!xt|The author thanked Bob Marley, Sinéad O'Connor[,] and her friends}}{{spnd}}introduces ambiguity about ''her''.
*Recast the sentence ("friend" case):
**To list two people: {{xt|The author thanked Bob Marley and her friend, Sinéad O'Connor.}}
***Or be more specific when possible (the commas here set off non-restrictive [[Apposition|appositives]]): {{xt|The author thanked her childhood friend, Sinéad O'Connor, and her mentor, Bob Marley.}}
**To list three people: {{xt|The author thanked Bob Marley, Sinéad O'Connor, and a friend.}}
***Clarity with gender-specific terms such as ''mother'' can be tricky; {{!xt|The author thanked her mother, Kim Thayil, and Sinéad O'Connor}} is unclear because readers may not know [[Kim Thayil]] is male and wouldn't be the same person as the mother.
***Clearer: {{xt|The author thanked Kim Thayil, Sinéad O'Connor, and her own mother}} or {{xt|The author thanked her mother and musicians Kim Thayil and Sinéad O'Connor}}.