Using Hyphens

Good morning, dear readers! Here’s another installment of my Monday grammar checkup posts, this one on using hyphens in compound (multi-word) adjectives, those that come right in front of a noun and modify / describe it.

I often see this in blogs: “She is an 11-year old child.”
Or this: “She is an 11 year-old child.”
And even more often: “She’s an 11 year old child.”

The rule is simple:  Use hyphens to connect all the words that work together to describe the noun that follows them.

In the example above, in order to make sense of the words “11 year old,” we need to connect all three words. It makes no sense to say she is an 11 child or an 11 year child. We cannot say she’s a year-old child, not when she’s 11. The full description contains all three words.

Another example:

                     John’s building three-level condos.
                     John’s building three level condos.

Without the hyphen, a reader could infer that John is building three condos that are level (as opposed to crooked). Doubtful, right? In order to show that he’s building condos that have three levels, we need to hyphenate “three level” in that sentence.

The examples shown below are some of the most commonly used phrases, showing them as hyphenated when coming before a noun, and not hyphenated when they revert to their usual form.