If you just asked yourself “What’s a modifier?” please don’t close your browser! There is something here for you, as well as for those few readers who paid attention in 9th grade English.
Modifiers are important to us because they appear in every JA document and most of us get them wrong at least half the time.
Grammatically speaking, modifiers are words or phrases that describe, qualify, clarify, or give more detail about another word or concept within a sentence. They function as adjectives or adverbs, but are different in the sense that they can be phrases or entire clauses of sentences.
In plain English, this means that modifiers are (generally) phrases that give more information about another word or phrase. For example, in this sentence the phrase “newly constructed” is modifying “tunnel”:
The newly constructed tunnel provides system redundancy.
In the following sentences, can you identify the modifiers?
The 3,465-foot tunnel crossed under two major roadways.
The tunnel was 3,465 feet long and crossed under two major roadways.
The crosstown railroad track was reclaimed for light rail use.
The decision-making process took about three weeks.
The night shift workers contributed significantly to the success of the project.
Here they are with modifiers bolded:
The 3,465-foot tunnel crossed under two major roadways.
The tunnel was 3,465 feet long and crossed under two major roadways.
The crosstown railroad track was reclaimed for light rail use.
The decision-making process took about three weeks.
The night shift workers contributed significantly to the success of the project.
There are two interesting lessons here. The first relates to the use of single words, combined words, and hyphenates as modifiers — and the second is a lesson about when a phrase isn’t a modifer. Let’s look at the first lesson first, shall we?
Modifiers often have a compound structure (two or more words that function together as one unit of meaning — e.g., “firehouse” has a different meaning than “fire” and “house” individually, but it was combined from the two words). Compounds can be open (night shift), closed (crosstown), or hyphenated (decision-making). Usually a compound starts out open, over time begins to be used with a hyphen, and then becomes a closed compound. To determine if something is an open, closed, or hyphenated compound, you must look it up in the dictionary.
The second lesson is about when a phrase is or is not being used as a modifier. This most often comes up in our size descriptions of tunnels, as in these two sentences:
The 3,465-foot tunnel crossed under two major roadways.
The tunnel was 3,465 feet long and crossed under two major roadways.
In the first sentence, “3,465-foot” is modifying “tunnel.” We know this because if we take out the measurement, the sentence is still a complete sentence (e.g., it expresses a full thought: The tunnel crossed under two major roadways).
In the second sentence, “3,465 feet long” is not a modifier, but instead, a critical part of the sentence. Try removing it, and you get “The tunnel was and crossed under two major roadways.”
When a modifier consists of two words/units functioning as one semantic unit, they generally must be hyphenated. Thus, the hyphen between “3,465” and “feet” in the first sentence.
(Note that technically, if you said “the 3,465-foot-long tunnel”, you would need the hyphen between “foot” and “long” as well. However, I’m not fighting that battle, as this correct usage is not generally observed in the industry.)
This can be a difficult concept, and certainly isn’t an easy one to explain. If you have questions about– or corrections to–my explanation, please do post a comment here or e-mail me and I’ll get back to you.
For more about the wonderful world of hyphens and modifiers, click on the category links at right. I’ve discussed this topic with more brevity in the past, and I’ve also previously posted about dangling modifiers. Thrilling, isn’t it?
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