The active voice sentence is "The servant is keeping my house tidy." Choose the option that best expresses this sentence in the passive voice.

Introduction / Context:
This question checks conversion from present continuous tense in the active voice to the corresponding passive voice form. The sentence describes an ongoing action where the servant is performing the task of keeping the house tidy. In the passive version, the focus should shift from the servant to the house, while preserving the idea that the action is still in progress.

Given Data / Assumptions:

• Active sentence: The servant is keeping my house tidy.
• Subject: the servant.
• Object: my house.
• Verb phrase: is keeping tidy (present continuous form of "keep").
• Adjective complement: tidy, describing the condition of the house.

Concept / Approach:
To convert a present continuous sentence into passive voice, we use the structure: subject (object of the active) + is/am/are + being + past participle of the main verb + by + original subject. The object "my house" becomes the subject in the passive sentence. The verb "is keeping" changes to "is being kept." The adjective "tidy" stays as a complement. We add the agent "by the servant" at the end to indicate who is performing the action.

Step-by-Step Solution:

Step 1: Identify the object in the active sentence: "my house." This will become the subject in the passive version. Step 2: Recognise the tense and aspect: "is keeping" is present continuous. The passive of present continuous is "is being kept" for a singular subject. Step 3: Keep the adjective complement "tidy" after the past participle because it describes the condition of the house. Step 4: Add "by the servant" to keep the agent. The final passive sentence becomes: "My house is being kept tidy by the servant."

Verification / Alternative check:
The resulting sentence "My house is being kept tidy by the servant" is grammatically correct and clearly shows present continuous passive voice. The focus is now on "my house," which is appropriate for a passive construction, and the original meaning that the servant is currently engaged in keeping it tidy is preserved. The structure "is being kept tidy" is standard.

Why Other Options Are Wrong:

Option B: "Keeping of my house tidy is done by the servant." is clumsy and unnatural, using an unnecessary nominalisation "keeping of" that exam boards usually discourage. Option C: "The servant had kept tidy my house." changes both tense and aspect to past perfect, which is not equivalent to the original present continuous meaning. Option D: "My house the servant keeps tidy." is active voice, not passive, and has an unusual word order more suited to literary style than to standard grammar questions. Option E: "The servant is tidy when keeping my house." changes the meaning, suggesting that the servant is tidy, not necessarily the house.

Common Pitfalls:
Common errors include forgetting to add "being" in continuous passive forms, which leads to incorrect structures like "is kept" instead of "is being kept" for an action happening right now. Another pitfall is trying to rearrange words without preserving tense and aspect, resulting in sentences that sound active or change the meaning. Learners should always identify the tense first, then apply the appropriate passive formula for that tense.

Final Answer:
The correct passive sentence is My house is being kept tidy by the servant.