Where do I place commas in English sentences?

Note: There is debate whether or not one should include a comma, often referred to as the “Oxford comma,” separating the final two items in the series. Some style guides may instruct you to omit the comma unless doing so would lead to confusion in distinguishing items. Consult your style guide to see what is appropriate for your paper. Most importantly, be consistent.

COMMA OPTIONAL:
The VR city contains skyscrapers, houses, churches, and various other buildings. (Oxford comma)
OR
The VR city contains skyscrapers, houses, churches and various other buildings. (no Oxford comma)
COMMA REQUIRED: The project was designed and carried out by professors at Harvard, William and Mary, and Yale.

Tip: If you can add the word “and” between the adjectives, this signals that they are interchangeable.

COMMA NECESSARY: Immense, ingenious Count Fosco is the main adversary in Wilkie Collins’s The Woman in White.

NO COMMA: The lab features advanced custom eye-tracking equipment.

Note: You do not need to put a comma before “because.”

COMMA NECESSARY: Agatha Christie is perhaps the most well-known writer of the Golden Age of Detective Fiction, and her works have been translated into more than 100 languages.

COMMA NECESSARY: Participants were not permitted to talk during the experiment, nor were they allowed to discuss the experiment between tasks.

COMMA OPTIONAL: The interview questions were designed to direct the conversation toward the main research aims of the study but not influence the participants to respond a certain way.

In this example, no comma is necessary because the clause following the conjunction “but” is dependent/subordinate, meaning that it cannot stand on its own. However, you may add a comma if you wish to emphasize the second portion of the sentence.

Note: There are multiple ways to correct a comma splice. Below are a few examples.

INCORRECT: The Romantic era stretched from the late 18th into the mid-19th century, it is often interpreted as a reaction the Industrial Revolution.

CORRECT: The Romantic era stretched from the late 18th into the mid-19th century. It is often interpreted as a reaction the Industrial Revolution.

CORRECT: The Romantic era stretched from the late 18th into the mid-19th century; it is often interpreted as a reaction the Industrial Revolution.

CORRECT: The Romantic era stretched from the late 18th into the mid-19th century, and it is often interpreted as a reaction the Industrial Revolution.

In 2019, James B. Goodenough, M. Stanley Whittingham, and Akira Yoshino were awarded the Nobel Prize in Chemistry.

However, the results indicated that our hypothesis was incorrect.

Cunning and resourceful, Becky Sharp is widely considered one of the most memorable female characters in Victorian literature.

Due to time constraints, we were unable to conduct a second round of interviews.

While some scholars have acknowledged that migrants and their descendants may play an important role in advocating for and sustaining specific city partnerships, few have examined that factor in depth.

The “trolley problem,” which challenges utilitarianism and deontological ethics, has been referenced in contemporary debates surrounding autonomous vehicle design.

Albert Einstein, who developed the theory of relativity, immigrated to the United States in 1933.

Note: Relative clauses following the word “that” are always considered essential.

The idea that living organisms can originate from non-living matter is rejected by most modern biologists.

The U.S. presidential candidate who wins the popular vote does not necessarily win the election.

INCORRECT: The part of Hans Beckert in the 1931 masterpiece M, was Peter Lorre’s first major starring role.

INCORRECT: The English city of Bath, was a popular spa resort during Jane Austen’s time.

Simply remove the commas to correct the sentences.

Faulkner wrote, “The past is not dead. It’s not even past.”

“The whole is greater than the sum of its parts,” said Aristotle.

Note: British English calls for single quotation marks and puts the comma outside the quotation marks.

New Braunfels, Texas, is a sister city of Braunfels, Germany.

On November 9, 1989, the Berlin Wall fell.

The Schreibwerkstatt is located at Neuer Graben 7, Osnabrück, Germany.

Jane Doe, PhD, gave the opening address.

Most importantly, use commas to avoid any possibility of confusion!
Did you see Steve, Martin? =/= Did you see Steve Martin?