To separate adjectives used in the predicative position
Adjectives used in the predicative position are always separated by commas.
- He is tall, dark and handsome.
- That was a lovely, long, cool drink.
Sometimes commas are not used between the last two adjectives which are usually separated by a conjunction like and or or.
Commas are sometimes dropped between short adjectives.
In direct speech
A comma is generally used between a reporting verb and a piece of direct speech.
- Looking at the painting, she said, ‘I like this one.’
If the reporting verb follows a piece of direct speech, we usually use a comma instead of a full stop before the closing quotation mark.
- ‘I don’t like this,‘ said Jane.
Large numbers are often divided into groups of three figures by using commas.
- 5,768 (NOT 5.768)
- 6, 567, 873
Commas are sometimes not used in four figure numbers.
- 5,378 or 5378
Commas are never used in dates.
- The Year 1953 (NOT The Year 1,953)
Cases where commas are not used
Commas are not used before that, what, where etc in indirect speech structures.
- Nobody realized that the child was missing. (NOT Nobody realized, that the child …)
- She didn’t know what to do. (NOT She didn’t know, what to do.)
Commas are not used between two grammatically independent sentences. Instead we use a full stop or a semicolon.
- The blue dress was cheap. On the other hand, the pink dress was better. OR The blue dress was cheap; on the other hand, the pink dress was better. (NOT The blue dress was cheap, on the other hand, …)