Improving your English punctuation 2
When to use commas in English
1. To separate items in a list
We need coffee, tea, sugar and milk.
British English writers do not normally put a comma before "and", although in American
English, a comma can be used.
"We need coffee, tea, sugar, and milk."
2. To separate clauses which are related in meaning
Do you know the answer, or should I ask Tony?
Where the clauses are short, commas are not used:
"I was tired so I went home."
3. After introductory phrases
Unfortunately, I cannot send you the information.
4. Before and after a word or phrase that interrupts the main clause
Some children,if they are gifted, attend special schools.
5. Before and after non-defining clauses
The factory workers, who were in a meeting, decided to accept the pay offer.
= All the factory workers were in a meeting.
Compare with a defining clause (which restricts the noun).
The factory workers who were in a meeting decided to accept the pay offer.
= Only the factory workers who were in a meeting decided to accept the offer: those workers who were not in the meeting didn't decide to accept the offer.
6. To show millions, thousands and hundreds
5, 890, 2811
10, 050