Understanding the Need for an Adverb

The question asks us to select the appropriate adverb for the underlined word "obvious" in the sentence: "He led me to the room that had obvious been built later than the rest of the house."

In this sentence, the word "obvious" is placed before the verb phrase "been built". The word needed here must modify the verb phrase, telling us *how* the room appeared to have been built later. Words that modify verbs, adjectives, or other adverbs are called adverbs.

The word "obvious" is an adjective. Adjectives describe nouns or pronouns. For example, you might say "an obvious mistake" (obvious describes the noun 'mistake'). However, in our sentence, "obvious" is attempting to modify the verb phrase "had been built", which requires an adverb.

Therefore, we need to convert the adjective "obvious" into its corresponding adverb form.

Identifying the Correct Adverb Form

Let's look at the given options and determine which one is the correct adverb form of "obvious" that fits the sentence context:

1. obliviously: This is the adverb form of the adjective "oblivious," which means unaware or unconscious. This meaning does not fit the sentence about how a room was built.
2. obliviousness: This is a noun form, meaning the state of being oblivious. Nouns do not modify verbs.
3. obviousness: This is also a noun form, meaning the state or quality of being obvious. Nouns do not modify verbs.
4. obviously: This is the adverb form of the adjective "obvious." It means in a way that is easy to see, understand, or recognize; clearly. This meaning perfectly fits the sentence, indicating that it was clear or evident that the room had been built later.

Analyzing the Sentence with the Correct Adverb

Replacing "obvious" with "obviously" gives us the sentence: "He led me to the room that had obviously been built later than the rest of the house."

In this revised sentence, "obviously" functions correctly as an adverb, modifying the verb phrase "had been built" to describe the manner or appearance of the construction – it was clearly built later. This makes the sentence grammatically correct and conveys the intended meaning.

Conclusion on Selecting the Appropriate Adverb

Based on the requirement for a word to modify the verb phrase "had been built" and the analysis of the options, the appropriate adverb for the underlined word "obvious" is "obviously".

Revision Table: English Grammar Word Forms

Understanding different word forms like adjectives and adverbs is crucial for correct sentence construction. Here's a quick look at how words change form.

Additional Information: Adverbs in English Sentences

Adverbs play a vital role in adding detail to sentences. They can tell us how, when, where, why, or to what extent an action is performed or a quality exists.

• Modifying Verbs: Adverbs commonly modify verbs, describing the action. Example: She sings beautifully. (How she sings)
• Modifying Adjectives: Adverbs can intensify or qualify adjectives. Example: He was extremely happy. (How happy)
• Modifying Other Adverbs: Adverbs can also modify other adverbs. Example: She finished the race very quickly. (How quickly)
• Placement: The position of an adverb can vary in a sentence, depending on what it is modifying and the type of adverb. Adverbs modifying verbs often appear after the verb or verb phrase, or sometimes at the beginning or end of the sentence, or before the verb (especially adverbs of frequency or certain adverbs like 'obviously').
• Forming Adverbs: Many adverbs are formed by adding "-ly" to an adjective (e.g., quick > quickly, careful > carefully, obvious > obviously). However, there are also many adverbs that do not end in "-ly" (e.g., fast, hard, well, very, often, never).

In the sentence "He led me to the room that had obviously been built later...", the adverb "obviously" is placed before the main verb phrase "been built," which is a common and acceptable position for adverbs like this, emphasizing the clarity of the observation about the building's age.