Question

Which uses the correct modifiers for formal writing? Gas prices rose steep enough to make Jack think twice about driving all the way across the country. Gas prices rose steeply enough to make Jack think twice about driving all the way across the country.

Answer 1

The second choice, Gas prices rose steeply enough to make Jack think twice about driving all the way across the country, is the correct answer. Steeply is the correct adverb to use.