Final answer:
In the sentence 'They are very silly,' 'very' is the adverb that modifies the adjective 'silly', emphasizing the degree to which 'they' exhibit the quality of being silly.
Step-by-step explanation:
In the sentence “They are very silly,” the word “very” serves as the adverb. Adverbs can modify verbs, adjectives, or other adverbs, providing additional information about the manner, place, time, frequency, certainty, or degree of the action or condition. In this context, “very” is qualifying the adjective “silly”, which describes the subject “They.” It emphasizes the degree to which ‘they’ are silly.
It's important to note that not all adverbs end in -ly. While many do (like “quickly” or “suddenly”), others like “very” do not. When assessing whether a word is an adverb, consider its function in the sentence rather than its form. In addition, remember the role of subject/verb agreement, ensuring that your subject and verb match in number and tense, even when other words or phrases might come between them.