Final answer:
To convert sentences into passive voice in present perfect tense, use the auxiliary 'to be' plus the past participle of the verb, often including 'by' if the performer of the action is mentioned. The sentences provided have been successfully converted to passive voice.
Step-by-step explanation:
Converting Sentences to Passive Voice
When converting sentences from active voice to passive voice, especially in the present perfect tense, it is important to recognize that the subject receives the action rather than performing it. This involves using a form of the auxiliary verb 'to be' and the past participle of the main verb, often accompanied by 'by' to indicate the doer of the action.
Completed Passive Sentences:
- The ground has been cleared of all the protesters who had gathered there.
- The books have been arranged on the shelf.
- The computer has been updated by a computer engineer.
- This car has been designed by an expert.
In each case, the focus is on the fact that the action has been completed, not on who completed it. Recognizing the correct passive voice construction in sentences is essential for creating a polished and stylistically appropriate writing, as seen in the examples provided.