How does a hyphen differ from a dash? a hyphen separates a prefix ending in a vowel from a root word beginning with a vowel; a dash does not a hyphen introduces main ideas; a dash separates items in a series a hyphen introduces a long quotation; a dash introduces short quotations a hyphen signals a degree of pause; a dash only signals a dramatic effect

a hyphen separates a prefix ending in a vowel from a root word beginning with a vowel; a dash does not

Explanation:

You should use a hyphen to connect a prefix to another word if the prefix ends in a vowel and the base word also begins with one.

e.g. "pre-eminent," “co-own,” "anti-immune".

You cannot use a dash with these words.    

william mckinley

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benjamin harrison

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