Comma is is an important grammatical tool which is used to figure out which words have to go together in a sentence and which parts in a sentence are more important. Using commas incorrectly user may confuse the reader and the importance of the sentence.

Rule 1:

To separate words, in a list, though they are often omitted before and. For example:

  • A bouquet of red, pink and white roses.
  • Tea, coffee, milk or hot chocolate.
Rule 2:

To separate phrases and clauses. For example:

If you keep calm, take you time, concentrate and think ahead, then you are likely to pass your test.

Rule 3:

Before and after a clause or phrase that gives additional, but not essential, information about the noun it follows. For example:

  • The Pennine Hills, which are very popular with walkers, are situated between Lancashire and Yorkshire.
  • NOTE: Do not use commas before and after a clause that defines the noun. Example: The hills that separate Lancashire from Yorkshire are called the Penninies.
Rule 4:

To separate main clauses, especially long ones, linked by conjunction such as and, as, but, for, or. Example:

We had been looking forward to our holiday all year, but unfortunately it rained every day.

Rule 5:

To separate an introductory word or phrase, or an adverb or an adverbial phrase that applies to the whole sentence, from the rest of the sentence. Example:

  • Oh, so that’s where it was.
  • As it happens, however, I never saw her again.
  • By the way, did you hear about Rakesh’s car?
Rule 6:

To separate a tag question from the rest of the sentence. For example:

  • You live in Bristol, right ?
  • It’s quite expensive, isn’t it ?
Rule 7:

Before or after ‘he said’, etc. while writing down conversation. Example:

‘Come back soon’, she said.

Rule 8:

Before a short quotation. For example:

Disraeli said, ‘Little things affect little minds’.

Rule 9:

If in single part of speech, there are three words and they come one after another then comma is used. If there is and/or in the last, no comma is used. For example:

He is always eating, drinking and dancing.

Rule 10:

If a word is repeated, comma is used. For example:

Go, go, I don’t need you.

Rule 11:

Sometimes in a sentence there are words, where comma is required to avoid confusion. For example:

  • What he is, is known to me.
  • What he does, does not suit me.
  • What he did, was quite clear.
  • What should be done, should be done.
Rule 12:

Before and after apposition. For example:

  • I, Mohan, am a student.
  • Rajendra Prasad, the first President of India, was a great man.
  • He, the son of a rich man, is very proud.
Rule 13:

in fact, in short, for example, therefore, however, of course, too, moreover, for instance, on the contrary, by the way, comma is used. For example:

  • In fact, he is a good singer.
  • I love you, too.
  • I, too, have been to Paris.

NOTE: If too is used as adverb of degree, comma is not used. For example:

  • This is too much for me.
  • The news is too good to be true.
Rule 14:

After dates comma is used. Example:

  • April 20, 2017.
  • 20 April, 2017

If only month and year is given, comma may be used or not. For Example:

  • He was born in March, 2010.
  • He was born in March 2010.
Rule 15:

After salutation and words of leave-taking comma is used. For example:

  • Dear Suresh,
  • Yours sincerely,
  • Yours faithfully,
  • Yours truly
  • Sincerely yours,
Rule 16:

In case of name and title comma is used. Example:

  • Pro.T.P.Sinha, M.A.,Ph.D. has joined today.
  • Sri Singh, I.A.S. is our new S.D.O.
Rule 17:

In some sentence, verb is missing. Use comma after subject. For example:

  • I like fish; my friend, chicken.
  • I am going today; you, never.
  • He is a Rajput; she, a Brahmin.
Rule 18:

TO separate co-ordinate clauses in a compound sentence. For example:

  • He came, he saw, and he conquered.
  • I came, I saw, I conquered.
Rule 19:

Use of comma with respect to adverbial phrase, participle phrase, absolute phrase. For example:

  • At present, I have nothing to care for.
  • At last, he succeeded.
  • Having worked hard, he felt tired.
Rule 20:

Use of comma with respect to adverbial clause, non-finite/verb-less construction. For example:

  • If he comes to me, I shall help him.
  • When I was bachelor, I lived by myself.
  • When in Rome, do as the Romans do.