Fist check out our lesson video on Vital Noun Modifiers.
Essentially a vital modifier provides necessary information to identify the noun, where a non-essential noun modifier adds descriptive details.
The best way to check whether a modifier is essential or not is by restating the statement without the modifier.
In college, we heard a lecture by a woman who had won the Pulitzer prize.
If you drop the clause it simply reads:
In college, we heard a lecture by a woman.
This lecturer went from one in a small group of women to all the women in the world. Thus, the modifier is essential because taking it out drastically changes our understanding of the noun.
The Touch Rule
When modifiers modify a noun they must be adjacent (or touch) the noun they modify. This rule is one of the most important grammar rules to know. When the noun modifier does not touch the noun it modifies it is called a misplaced modifier.
However, like all rules, this rule has exceptions. A vital noun modifier always has logical priority over a non-vital noun modifier, and therefore could prevent a non-vital modifier from “touching” the noun by coming between the non-vital modifier and the noun. Be sure to watch our lesson video if you haven't already.
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