Final answer:
An en dash can be used to show a range, indicate an incomplete thought, or emphasize a phrase.
Step-by-step explanation:
An en dash (-) can be used to show a range between two numbers, such as 10-15. For example, the temperature range today is 70-80 degrees Fahrenheit.
An en dash can also be placed at the end of a sentence to show an incomplete thought or interruption. For instance, She realized that she forgot her keys on the way home--and had to go back to get them.
An en dash can also be used on either side of a phrase to add emphasis, such as 'The winner--John Smith--received a trophy'.
Therefore, the correct answer is all of the above.
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