Punctuation is a device in writing to help your readers understand better what you have expressed in your writing. There are certain punctuation rules you need to follow in order to make your meaning clear.
The colon is a formal introduction.
e.g. One important factor is missing: honesty.
The colon is used to introduce a single word or phrase for emphasis or dramatic effect.
e.g. He had one thing to live for: his ambition to become the chairman of the company.
e.g. All her life she wanted one thing for her daughter: happiness.
The colon is used to substitute “as a result.”
e.g. He made some bad investments: he became bankrupt.
e.g. He worked very hard: soon he became the head of the section.
The colon separates two independent clauses when one explains the other.
e.g. You cannot trust him: he is a very dishonest person.
e.g. This project is very easy: you can do it in just a few hours.
The colon is NOT used after a linking verb or after a preposition.
e.g. The two sources of physical pain are injury and disease. (NO colon after the linking verb are)
e.g. There are two sources of physical pain: injury and disease. (colon here)
e.g. The man was guilty of stealing the money, abducting the child, and burning down the house. (NO colon after the preposition of; do not interrupt the normal flow of thought by adding a colon)
e.g. The man was guilty of several crimes: stealing the money, abducting the child, and burning down the house. (colon is used here to complete the flow of thought in the first part of the sentence)
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