Colons

Colons may also be used to connect independent clauses when the logical link between them is immediate, as when the first clause makes a general assertion and the second clause provides an example:

　　This form of social organization creates habits that are carried into the business world: Chinese companies are literally families.

　　You may also use colons between closely connected sentence elements other than two independent clauses, though this should be done sparingly:

　　The data point to only one conclusion: fraud.

　　In essays, colons are used most frequently to introduce quotations. If you use a colon, you need to make sure that the quotation is not integrally connected to the grammar of the introductory sentence:

　　In the "Apology" Socrates says: "The unexamined life is not worth living. . ." （39）.

　　In the "Apology" Socrates says, "The unexamined life is not worth living. . ." （39）.

　　In the "Apology," Socrates states his fundamental principle: "The unexamined life is not worth living. . ." （39）.

　　Sometimes a colon is used incorrectly to introduce a list:

　　Globalization of retail trade is being encouraged by several treaties and trade agreements such as: the General Agreement on Trade in Services （GATS）, the North American Free Trade Agreement （NAFTA）, the European Union （EU）, and the Andean Pact.

　　Globalization of retail trade is being encouraged by several treaties and trade agreements such as the General Agreement on Trade in Services （GATS）, the North American Free Trade Agreement （NAFTA）, and the Andean Pact.

　　Several treaties and trade agreements are facilitating the globalization of retail trade: the General Agreement on Trade in Services （GATS）, the North American Free Trade Agreement （NAFTA）, the European Union （EU）, and the Andean Pact.

　　Again, the reason the second revision works is that the words before the colon stand by themselves as an independent clause.