1、冒号用于对后面内容的介绍或解释,如 This is her plan: go ...
2、冒号用于名单之前,特别是一个竖排的名单。 We transferred three ...
3、冒号用于一个正式的引用之前。如 The professor said: “It was ...用来列举事项。如：（1）The room was furnished with simplest essentials: a bed, a chair and a table.房间里只放了一些最简单的必需品：一张床、一把椅子和一张桌子。（2）My dad has three dependants: my mother, my sister and me.我父亲有三个家眷：我母亲，我姐姐和我。（3）He doesn’t just write for fun: writing is his bread and butter.他写作不仅仅是为了好玩，写作是他的生计。
4、冒号也可用于商业或正式信函的称谓后面,如 Dear Mr. Lee:(美国英语中,信件或...在美式英语中，书信开头称呼后面可以用冒号。如：Dear Mrs. Wang:I would like to thanks you for …
5、冒号用于数字时间的表示,如16:45 或 4:45 p.m.
