Some words in the English language can be used both as adjectives and adverbs. Among these are straight, hard, backward, far, high, and close.

While this may create some confusion at times, just remember that an adjective describes a noun or pronoun while an adverb describes a verb, an adjective, or another adverb.

Examples:

Most birds fly high. (adverb)

However, there are some who cannot fly even over the high walls of houses. (adjective)

Questions like What kind? Which one? How many? and How much? need adjectives as answers.

Questions like Where? What? In what way? and To what extent? require adverbs as answers.

Examples:

Trees shed off their leaves early in fall. (adverb)

We have to rake the leaves before the early visitors arrive. (adjective)