If you know that "precautions" is a noun,

[July]

and that "roar" in "a terrible roar" is also a noun,

you know more than my son's high school English teacher. She believes they are verbs.

[miss_american_pie]

1. Oy

Maybe someone should get her a copy of Where the Wild Things Are. :eyes:

[beyurslf]

2. Did she explain how? And did that terrible an adverb not an adjective?

For that matter, it would make "a" an adverb also.