Punctuation

Punctuation helps readers break writing into logical units, making it easier to follow. Punctuation includes all the conventional signs used to separate words: spaces, first-line indentation of paragraphs, blank lines, uppercase letters, and various marks or stops （commas, periods, semicolons, and so on）. Punctuation is conventional rather than scientific, and has evolved over time. The earliest written languages, in fact, had no punctuation at all, writers just RANWORDSTOGETHERFORASLONGASTHEYCAREDTOWRITE （every so often a bold pioneer would introduce a reader-friendly innovation like LowerCaseLetters or spaces between words）.

　　In the modern world punctuation is an important thing to get right in formal writing. Readers of formal writing interpret punctuation mistakes as a sign of poor education or carelessness, and in either case tend to discount the work's validity. Here Nuts and Bolts presents a brief treatment of the use and abuse of the major punctuation marks.

　　Choices in punctuation can greatly affect meaning. Indeed if you mess with punctuation enough you can turn the meaning upside down:

Dear John,

I want a man who knows what love is all about. You are generous, kind, thoughtful. People who are not like you admit to being useless and inferior. You have ruined me for other men. I yearn for you. I have no feelings whatsoever when we're apart. I can be forever happy—will you let me be yours?

Gloria
Dear John,

I want a man who knows what love is. All about you are generous, kind, thoughtful people, who are not like you. Admit to being useless and inferior. You have ruined me. For other men, I yearn. For you, I have no feelings whatsoever. When we're apart, I can be forever happy. Will you let me be?

Yours,

Gloria

　　Fortunately, repunctuating doesn't usually have such drastic consequences. But punctuating properly is still a vital part of good writing, and it's something that gives students fits and starts. Here we want to focus on just a few of the most common punctuation troublespots: comma splices, semi-colons, colons, dashes, and parentheses.

Comma splices

Semicolons

Colons

Dashes

Parentheses

Question marks and exclamation marks

Italics and emphasis

Emphasis with quotation marks

Single quotation marks

Emoticons