When to Use a Comma

A Mini Grammar Guide: When to and When Not to Use a Comma?

It is essential to know correct grammar rules if you wish to avoid some of the most obvious mistakes while writing. Here are the rules of using a comma in different cases.
Penlighten Staff
Last Updated: Mar 10, 2018
comma sign
It is a common knowledge that English is a funny or a difficult language with no specific rules on the pronunciation. However, the rules of English grammar for proper sentence constructions and speech are well set. Along with the proper use of figures of speech or words in a sentence, it is also essential to use the punctuation marks correctly and at the proper places. Comma is one of the commonly used punctuation marks.

Rules for Comma Usage

A comma is used to separate two different terms, parts of sentences, words, etc. A period completes the sentence, whereas, a comma is used show a continuation to a different part of a sentence. Confused? Well, take a look at rules.

To separate words, word groups, adjectives, series, etc.
e.g.: She was a young, beautiful girl.
e.g.: His friends, colleagues, and family were present.
e.g.: USA, India, England, France, and Japan were the participating nations.

Used before a coordinating conjunction.
e.g.: While I am at work, my younger child watches television, and the older one is off to school.
e.g.: It is essential to have a balanced diet, exercise regularly, and visit the doctor at regular intervals.

To separate two clauses.
e.g.: Although born an aristocrat, he was a humble man.
e.g.: Mary, the most intelligent girl at school, had fallen ill.

Used immediately after certain adverbs in a sentence.
e.g.: However, this is not practical.
e.g.: Therefore, you should have a proper diet.

Used before quotes or expressions.
e.g.: Mrs. Dewitt said, "Wait! Help me with this!"
e.g.: The teacher asked, "Do you know when to use a comma?"

Used when writing dates, addresses, etc.*
e.g.: Today is Monday, April 14, 1914
e.g.: 70, Browning Street, Jacksonville, Florida

Used while writing some proper nouns, titles, names.
e.g.: Diana, Princess of Wales
e.g.: New Delhi, India

In some countries, a comma is used for writing large numbers.
e.g.: 10,00,000 or 1,000,000

* It should be noted that there is an exception that a comma is NEVER used while writing ZIP codes, phone numbers, page numbers, and house numbers

Miscellaneous Examples
  • e.g.: Once upon a time, there was a kingdom.
  • e.g.: I wish, Dad, that you would hear this.
  • e.g.: To, The Principal, (in a letter)
  • e.g.: Yes, I will!
  • e.g.: Mr. Stevens, M.D, was present.
Putting these rules into practice will definitely help you in avoiding errors in writing. Good luck!