The Dash
12 rules
No Capitalization After a Dash
Do not capitalize the first word after a dash unless it is a word that is always capitalized (such as a proper noun or 'I'). The dash is a mid-sentence punctuation mark, not a sentence-ending one.
Dash for a Broken or Incomplete Sentence
Use a dash when the sentence structure is broken — that is, when a sentence is begun and is not completed. The speaker starts a thought, abandons it, and begins a new one. The dash marks the point where the original thought was abandoned.
Dash for Interruption When the Speaker Continues
When an interruption occurs and the speaker does not stop talking, use a dash for the interruption and a second dash in front of the continuation of the original thought. If the speaker picks up the thought after an intervening exchange (another speaker's words), paragraph the continuation and use a dash in front of it. Even if a few words repeat, if the sentence still represents one thought, use a dash to show the continuation. But if the sentence completely starts over, begin a new sentence without a dash.
Dash After a Topic Word When the Sentence Breaks Off
When a sentence begins with a word or words that represent the topic of the conversation and the sentence is then broken off, use a dash after the topic word(s). The speaker introduces a subject but then restructures the sentence.
Dash Before 'Correction,' 'No,' or 'Strike That'
Put a dash before and a period after words like 'correction,' 'no,' or 'strike that' when they are used to signal an interruption or self-correction of the sentence. The corrected sentence that follows begins as a new sentence.
Dash or Ellipsis When a Speaker Trails Off
When a person trails off and does not finish a sentence, use a dash or ellipsis. When the word 'but' is used before the trailing off, put no punctuation before 'but' and a dash or ellipsis after it. When the word 'so' is used before the trailing off, put a semicolon or a period before 'so' and a dash or ellipsis after it. The choice between dash and ellipsis is a style preference.
Dashes Around a Complete Thought Dropped Inside a Sentence
When a complete thought is dropped inside another sentence, surround it with a pair of dashes. If the sentence within the dashes is a statement, do not use any terminal punctuation before the second dash. If the sentence within the dashes is a question, use a question mark before the second dash. If the sentence outside the dashes is asking a question, put a question mark at the end of that sentence without regard to the punctuation inside the dashes.
Dash Before Summary Words
When one word or a few words are used after the sentence to summarize its whole idea (summary words), use a dash before them. Often a pronoun (each, these, them, all) refers back to multiple items in the sentence. The dash signals the shift from specifics to summary.
Dashes Replace Commas When the Element Has Internal Commas
When an element that needs commas around it (such as an appositive or nonessential clause) also has internal commas, use a pair of dashes to replace the commas around the element. This prevents confusion between the separating commas and the internal commas.
Dash With Appositives Far Removed, Noun Clauses, or After a Short Sentence
When an appositive is used to rename a word that is very far removed from it, use a dash before the appositive or a pair of dashes around it to clarify the connection. When the appositive is a noun clause, use the same dash treatment. When an appositive renames the subject of the sentence and comes after the sentence has finished (even when the sentence is short), use a dash before the appositive.
No Commas, Colons, or Semicolons With Dashed Material
Commas, colons, and semicolons are not used to introduce or end dashed material, even though they might have been used if no interruption had occurred. A period may precede a dash only if the period is part of an abbreviation. The dash replaces whatever punctuation would have appeared at the point of interruption.
Dash Placement With Quotation Marks
Place dashes inside or outside of quotation marks according to their relationship to the quoted material. Most often, quoted material being cited is interrupted by the speaker for remarks or clarification, and the dashes will be outside the quotation marks. When previous transcripts are read in court and the original quoted material contains dashes, use the dashes within the quotation marks if the court reporter knows this.