Knowing when to hyphenate numbers is important because the correct use of the hyphen helps your reader to understand which numbers are part of a given adjective and avoids any ambiguity.
Let’s look at the example on the left.
Is the guy working twenty shifts that are each four hours long, twenty-four shifts that are each an hour long? Or shifts that last twenty-four hours in total?
As you can see, where you place the hyphen in the number can make a significant difference to the meaning of the sentence.













When it comes to hyphen use, many writers purposely choose to entirely omit this dreaded punctuation mark in fear of using it incorrectly.