Understanding sentence voice is a key part of English grammar. Sentences can be in either active voice or passive voice. Changing the voice means rearranging the sentence elements while keeping the meaning the same.

What are Active and Passive Voice?

• Active Voice: The subject of the sentence performs the action. The structure is typically Subject + Verb + Object. For example: The dog chased the ball. (Dog performs the action of chasing).
• Passive Voice: The subject of the sentence receives the action. The structure is typically Object (becomes subject) + Verb (usually a form of 'be' + past participle) + by + Agent (original subject). For example: The ball was chased by the dog. (Ball receives the action of being chased).

Analyzing the Passive Voice Sentence

The given sentence is: "The lock has not yet been repaired by the locksmith."

Let's break down its structure:

• Subject (receiver of action): The lock
• Verb Phrase: has not yet been repaired (Present Perfect Passive)
• Agent (doer of action): the locksmith (introduced by 'by')

The tense is Present Perfect, indicated by "has been repaired". The 'not yet' shows negation and a time frame.

Steps to Convert Passive Voice to Active Voice

To change this passive sentence to active voice, we need to follow these steps:

1. Identify the agent (the doer of the action) in the passive sentence. This is usually in the 'by + agent' phrase. Here, the agent is "the locksmith".
2. Make the agent the subject of the active sentence. So, the active sentence will start with "The locksmith...".
3. Identify the main verb in the passive sentence (the past participle) and the helping verbs (form of 'be' and tense indicators). Here, the main verb is "repaired", and the passive structure is "has been repaired" (Present Perfect Passive).
4. Change the verb phrase to the active voice equivalent, keeping the original tense. The Present Perfect Active form is Subject + has/have + past participle. Since the subject is "The locksmith" (singular), we use "has". The negation "not" and "yet" should also be included. So, the verb phrase becomes "has not yet repaired" or "has not repaired... yet".
5. Identify the subject of the passive sentence (the receiver of the action). This is "The lock".
6. Make this element the object of the active sentence. So, the active sentence will end with "...the lock".

Following these steps, the active voice sentence should be: "The locksmith has not yet repaired the lock." or "The locksmith has not repaired the lock yet."

Evaluating the Options

Let's look at the provided options and see which one matches the active voice conversion:

Based on the analysis, Option 2 correctly converts the passive voice sentence into the active voice while maintaining the original tense and meaning.

Revision Table: Mastering Voice Change

Additional Information on Sentence Voice

Changing the voice of a sentence is a common exercise in grammar. It's important to identify the tense of the original sentence first, as this tense must be maintained in the transformed sentence. The 'by + agent' phrase in a passive sentence tells you who performed the action; this agent becomes the subject in the active voice. If the agent is not mentioned in the passive voice (e.g., "The lock has not yet been repaired"), you might need to assume a general subject like "Someone" or "They" in the active voice, but in this case, the agent "the locksmith" is clearly given.

Common tenses and their voice changes:

• Simple Present: Active (Subject + Verb base/s/es) $\rightarrow$ Passive (Object + is/am/are + Past Participle)
• Simple Past: Active (Subject + Verb past form) $\rightarrow$ Passive (Object + was/were + Past Participle)
• Present Continuous: Active (Subject + is/am/are + Verb-ing) $\rightarrow$ Passive (Object + is/am/are + being + Past Participle)
• Past Continuous: Active (Subject + was/were + Verb-ing) $\rightarrow$ Passive (Object + was/were + being + Past Participle)
• Present Perfect: Active (Subject + has/have + Past Participle) $\rightarrow$ Passive (Object + has/have + been + Past Participle)
• Past Perfect: Active (Subject + had + Past Participle) $\rightarrow$ Passive (Object + had + been + Past Participle)
• Future Simple: Active (Subject + will + Verb base) $\rightarrow$ Passive (Object + will + be + Past Participle)

Practice is key to mastering sentence voice transformations.