Select the correct passive form of the given sentence.
“The architect could have been designing the building.”
Show answer & explanation
Correct answer: D
Explanation
Correct Answer: The building could have been being designed.
Explanation
The given sentence is in the active voice with a modal perfect continuous construction: Subject + modal (could) + have + been + V-ing + Object.
The rule to convert this form into passive voice is: Object + modal (could) + have + been + being + V3 (past participle) + (by + subject).
Following this structure, could have been designing changes to could have been being designed.