1. Semicolons分号 (;)
a. Use a semicolon between two complete sentencesthat are very closely related.
b. Use a semicolon before however and similar words (these words are called conjunctive adverbs) that show a relationship between two complete . sentences
大家注意，一定是complete sentence啊!Complete sentence must have a subject and a verb.
例句：I bet you though you wouldn’t have to learn another semicolon rule; however, you were wrong.
c. Use a semicolon before clauses that are introduced by for example, that is, nor namely.
例句：Olivia and Malory are excellent students; for example, they both made A’s on that really tough math test.
d. Use semicolons between clauses or phases that contain a lot of commas.通常是一堆并列句子的时候应用此原则。因为太多的comma会让读者产生断句的困难。
2. Colons 冒号(:)
a. Use a colon when you want to say “here come an example” or “here’s what I’m talking about.”
例句：This sentence is grammatically correct: I wonder if wolves actually wolf down their pizzas the way I wolf down mine. 读出来是那种“here’s what I’m talking about.”的感觉了吗?冒号后面的句子是进一步解释了前半句。
b. Use a colon before some lists. (这个一看就知道了吧…地球人都知道)
c. Use a colon before subtitles of books, articles, chapters, etc.
多么熟悉的面孔啊，很多article的title就是这样子的，例如，The title of the book is Michael Jordan: Basketball Superman.
顺便复习下title的大小写问题：实义词的首字母一定要大写，介词(the, a ,and, etc.)就不需要了，全部小写。当然，有些journal 投稿的时候会要求title全部字母大写(print)。
d. Use colons with expressions of time.
e. Use a colon in the greeting part of a formal letter or business letter.
f. Use a colon in literary references between volume and page or between chapter and verse.这个涉及到论文的reference部分的写作格式。找一篇APA格式的论文，翻到Reference部分就可以看到例子了。这个GMAT不太可能会考。
g. Use a colon with ratios.最明显的例子是比赛得分，例如：3:1。
h. Use colons to indicate dialogue when you’re writing a play or a script (and notice there are no quotation marks when you write dialogue this way). 写剧本的时候，人物对白写作方式。
i. Use a colon before a long, formal quotation. 例如，Governor Smith stated to the press: “… …”
j. Use a colon after words such as caution, wanted, or note.
Caution: slippery floor
Wanted: part-time waitresses and waiters
k. Capitalize the first word after a colon if it begins a complete sentence—and if you want to. Either way is okay; it's your choice.要是不能准确判断，就不要大写了，这样比较保险。