Final answer:
To convert sentences from active to passive voice, the object becomes the subject, the active verb is changed to a form of "be" plus the past participle, and the original subject can be added with "by." Examples in present perfect, past perfect, and future perfect tenses illustrate this conversion.
Step-by-step explanation:
Converting Active Voice into Passive Voice
To change a sentence from active to passive voice, you need to make the object of the active sentence into the subject of the passive sentence. Here's how you do it step by step:
- Identify the subject, verb, and object in the active voice sentence.
- Rearrange the sentence so that the object becomes the subject of the passive sentence.
- Change the verb to a form of "be" plus the past participle of the main verb.
- If necessary, add "by" followed by the original subject at the end of the sentence.
Below are examples with different tenses:
- Present Perfect: Active - "The researchers have discovered a new species." Passive - "A new species has been discovered by the researchers."
- Past Perfect: Active - "The team had completed the project before the deadline." Passive - "The project had been completed by the team before the deadline."
- Future Perfect: Active - "Scientists will have mapped the entire ocean floor by 2030." Passive - "The entire ocean floor will have been mapped by scientists by 2030."
Remember that while converting to passive voice, the focus is placed on the action or the object being acted upon rather than the doer of the action, which might be omitted if it's not important.