Final answer:
Dashes are used in writing to add emphasis to text, highlight an appositive without interrupting sentence flow, and clarify complex information. They provide a stronger break than commas or parentheses and are essential for effective communication.
Step-by-step explanation:
The dash is a versatile punctuation mark used to create a strong break in the structure of a sentence. Unlike commas or parentheses, dashes add emphasis to the text they precede or enclose, thereby highlighting additional information or an abrupt change in thought. This function is particularly useful when a sentence includes an appositive that already contains commas, avoiding potential confusion for the reader.
When used within sentences, definition technique often employs dashes to separate the term being defined from its explanation or clarification. For example, in the sentence 'The mitochondria—often called the powerhouse of the cell—are responsible for energy production,' the dashes emphasize the appositive phrase without interrupting the flow of the sentence. This method adds clarity and emphasis, helping the reader understand the importance of the appositive.
In educational writing, such as developing a brainstorming web or writing sentences to describe terms, dashes assist by structuring complex information. They can isolate examples, delineate lists, or provide additional context that might otherwise be jumbled with simpler punctuation. Dashes thereby enhance readability and comprehension, making them a valuable tool in effective communication.