Commas in English, Punctuation
When do we use commas?
1. separate independent clauses
The following conjunctions (so-called coordinating conjunctions) are used in such case: *
and, but, for, nor, or, so, yet
|The students asked for a second chance to rewrite the exam, but the teacher did not grant it.|
|2.1. after introductory subclauses||If you leave the door open, the dog might run away.|
|2.2. after introductory phrases||As a matter of fact, I’m going on vacation to Hawaii next week.|
|2.3. after introductory words||Unfortunately, he was convicted of a crime and put into jail.|
|3.1. when subclauses appear in the middle of the sentence.||Jill, who was sitting behind her desk, gave Tim a smile.|
|3.2. when phrases appear in the middle of the sentence.||We, as a matter of course, will contact your former employer.|
|3.3. when words appear in the middle of the sentence.||We have, however, found several severe errors.|
|4. to set off three or more words, phrases or mainclauses in a serious.||She went into the living room, sat down, and played chess on the computer.|
|5. to set off two or more coordinate adjectives, that is, the meaning does not change when the order is altered.||We had to travel over several narrow, winding, treacherous roads.|
|6. at the end of a sentence in order to indicate a pause.||He was merely ignorant, not stupid.|
|7. to set off a nonrestrictive (also non-defining) relative clause. **||Theodore Roosevelt, who was leader of the famous rough riders, became president in 1901.|
|8. when someone is addressed directly.||Susan, can you help me do the dishes please?|
|9. when a direct quotation is included.||Descartes said,“I think, therefore I am.”|
|10. to show an appositive. ***||Bill Clinton, former US president, is still very popular in Europe.|
|11. in dates.||Yes, July 17, 1972, was the date of his birth.|
|12. separate identical words.||How it is, is how it’s always been.|
|13. in front of tag questions.||Bring me the tools, will you?|
|14. after digits indicating thousands.||10,000|
|15.1. after a salutation in letters.||Dear John,|
15.2. after a farewell in letters.
- * Note that ‘but’ and ‘and’ do not take a comma when both are relatively short.
- ** restrictive relative clause= they tell us which person or thing, or which kind of person or thing, is meant;
non-restrictive relative clause = they tell us more about a person or thing that is already identified.
- *** When an appositive is only one word, no comma is needed.
Thanks to Kai.