In this active and passive voice question, choose the correct passive voice form of the sentence: The workers are building the house.

Introduction / Context:
Active and passive voice questions check whether you can transform a sentence while keeping the tense, meaning, and sense intact. The given sentence is in the present continuous tense in active voice. In competitive exams, you must recognise the tense and then build the correct passive structure with the appropriate helping verb and past participle form. Here you are asked to choose the passive voice form of the sentence The workers are building the house.

Given Data / Assumptions:

• Active sentence: The workers are building the house.
• Subject in active voice: the workers.
• Object in active voice: the house.
• Tense and aspect: present continuous (are building).
• We must convert to passive voice while keeping the meaning the same.

Concept / Approach:
In present continuous tense, the general pattern for active to passive transformation is: Subject + is/am/are + verb ing + object changes to Object + is/am/are + being + past participle + by + subject. The object becomes the new subject in passive voice and the original subject usually follows by. The verb building takes the past participle built. Because the object the house is singular, we use is being, not are being. These rules guide us directly to the correct passive structure.

Step-by-Step Solution:
Step 1: Identify the active voice pattern: The workers (subject) are building (verb) the house (object).Step 2: Move the object the house to the subject position in passive voice.Step 3: Keep the present continuous aspect by using is being for a singular subject.Step 4: Change building to the past participle built.Step 5: Place the original subject the workers after the preposition by.Step 6: The final passive sentence becomes: The house is being built by the workers.

Verification / Alternative Check:
Check tense and meaning. The workers are building the house describes an action in progress now. The house is being built by the workers also describes a present continuous action in progress. The doer and receiver of the action remain the same and the time reference does not change. No other option exactly preserves both the tense and the meaning with the correct form of the verb be and built. This confirms that the chosen option is correct.

Why Other Options Are Wrong:
The house was being built by the workers uses past continuous, not present continuous, so it changes the time reference. The house is built by the workers is simple present passive and suggests a general fact or habit. The house was built by the workers is simple past passive and refers to a completed action. All these forms do not match the continuous present action shown in the original active sentence and therefore they are incorrect for this transformation.

Common Pitfalls:
Candidates often forget to include being in continuous passive structures and write is built by mistake. Another common error is to change the tense from present to past just because the passive structure feels more natural. Some learners also reverse the word order and put by phrase incorrectly. Always identify the exact tense in the active sentence first and then apply the correct transformation pattern for that tense before selecting the final answer.

Final Answer:
The correct passive sentence is: The house is being built by the workers.