True. An adverb can indeed modify another adverb in a sentence. Adverbs are versatile parts of speech that provide additional information about verbs, adjectives, and other adverbs. When one adverb modifies another, it typically adds more detail or precision to the meaning conveyed. For example, in the sentence "She ran extremely quickly," the adverb "extremely" modifies the adverb "quickly," intensifying its meaning.
