21. Which word in the following sentence is a noun? The bird flew across the blue sky.
Answer: C
Bird is the noun in the sentence.
In the sentence "The bird flew across the blue sky," the word "bird" functions as a noun, representing a living organism.
A) across
The word "across" is a preposition in this context, indicating the movement of the bird relative to a location. It does not represent a person, place, thing, or idea, which is the defining characteristic of a noun.
B) flew
"Flew" is a verb that describes the action performed by the subject (the bird). Verbs express actions or states of being but do not serve as nouns, which are essential for identifying entities.
C) bird
"Bird" is the correct answer as it is a noun that represents a type of animal. It serves as the subject of the sentence, indicating what is performing the action of flying.
D) blue
The word "blue" is an adjective that describes the noun "sky." While it provides additional information about the sky, it does not qualify as a noun since it does not name a person, place, thing, or idea.
Conclusion
The word "bird" is definitively the noun in the given sentence because it identifies the subject that performs the action. All other options either serve different grammatical roles or do not name any entity, thus failing to meet the criteria of a noun.