1. Period or Full stop (.)
The primary usage of a period is to indicate sentence end. Its secondary usage is to indicate abbreviations like eg. or ie. There are cases where name titles are also followed by a period, especially in American English.
For example: Mr. Fowler (in American English)
2. Comma (,)
Use a comma to separate independent clauses in a sentence. For example:
The game was over, but the crowd refused to leave.
Comma is also used after introductory words, phrases or clauses that might come before the main clause. For example:
While I was eating, the cat scratched at the door.
If you are ill, you ought to see a doctor.
A pair of commas can also be used to separate a secondary clause from the main body of the sentence. For example:
John and Inga, the couple from next door, are coming for dinner tonight.
3. Colon (:)
A colon should be used at the end of a sentence to introduce one or more directly related ideas, such as a series of directions, a list, or a quotation or other comment illustrating or explaining the statement. For example:
The daily newspaper contains four sections: news, sports, entertainment, and classified ads.
4. Semicolon (;)
Use a semicolon to join related independent clauses in a compound sentence. For example:
Jane overslept by three hours; she was going to be late for work again.
5. Apostrophe (‘)
An apostrophe is used to indicated possession of any kind. For example:
Jane’s grades are better than her sister’s.
Here, if the apostrophe is not used, it will indicate plural Jane and plural sister, as if talking about more than one Jane or sister. If you need to indicate possession at the end of a plural word, like electors, just add it end the end of the word.
6. Ellipses (…)
Ellipses is indicated by three dots or periods. This indicates to the reader that a part has omitted from the quoted passage.
Never before, have so many … for so few.’ [Churchill’s famous speech]
Ellipses can also be used to indicate a pause, an unfinished thought or a trailing off into silence, when used in a written dialogue.
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