This question tests your understanding of transitive and intransitive verbs. Let's break down the concepts first.

Intransitive Verbs

An intransitive verb is an action verb that does not require a direct object to complete its meaning. The action of the verb is complete in itself.

Example: "The baby sleeps." The verb 'sleeps' is complete; there is nothing that is being slept.

Transitive Verbs

A transitive verb is an action verb that does require a direct object to receive the action and complete the sentence's meaning.

Example: "She ate an apple." The verb 'ate' requires the direct object 'an apple' to make sense.

Analyzing the Sentence: "The sky grew."

The verb "grew" is the past tense of "grow". In this sentence, it is used as an intransitive verb. It describes a change of state (the sky becoming darker at dusk, for example) and does not have a direct object. The sentence is grammatically correct but feels incomplete because it lacks a subject complement (like an adjective) to describe how the sky grew.

Evaluating the Options

Let's see which option best completes the sentence's meaning while using the verb correctly.

Option 1: grew bright
This adds the adjective "bright" as a subject complement. "The sky grew bright" means the sky became bright. This is a very common and correct use of the intransitive verb "grew". It completes the thought perfectly.

Option 2: NO CHANGE
"The sky grew" is grammatically correct as an intransitive verb but is stylistically weak and feels unfinished. It leaves the reader asking "grew what?" or "grew how?".

Option 3: grew to be
This phrase is often followed by an adjective (e.g., "grew to be large"). However, it is wordy and less direct than simply using "grew" with an adjective. "The sky grew to be bright" is acceptable but not the most concise or common phrasing.

Option 4: grew enough
"Enough" is an adverb here, modifying the verb "grew". "The sky grew enough" is grammatically possible but illogical and confusing. It implies the sky grew a sufficient amount, which doesn't make clear sense. What did it grow enough for?

Conclusion and Final Answer

The best correction is "grew bright". It correctly uses "grew" as an intransitive verb (linking verb) and provides the necessary adjective ("bright") to act as a subject complement, fully describing the change in the sky and creating a logical, complete sentence: "The sky grew bright."

Related Topics & Formulae

Linking Verbs: Verbs like 'grow', 'become', 'seem', 'appear', 'feel' often act as linking verbs. They connect the subject of a sentence to a subject complement (an adjective or noun) that renames or describes the subject. The formula is: Subject + Linking Verb + Subject Complement.

Subject Complement: A word or phrase that follows a linking verb and describes or identifies the subject. In the correct answer, "bright" is the subject complement describing "the sky".