They have built a perfect dam across the river.a)Across the river a pe...
A perfect dam has been built by them across the river.
Dam is an object so has been used and the they in the active voice has become them in the passive voice.
They have built a perfect dam across the river.a)Across the river a pe...
Explanation:
The correct answer is option 'B': "A perfect dam has been built by them across the river."
Here is the breakdown of the sentence and why option 'B' is the correct choice:
Subject and Verb Analysis:
- Subject: A perfect dam
- Verb: has been built
Tense and Voice Analysis:
- Tense: present perfect
- Voice: passive voice
Adverbial Phrase Analysis:
- Adverbial phrase: by them across the river
- This phrase indicates the location of the dam and the agent responsible for building it.
Sentence Structure Analysis:
- The sentence follows the subject-verb-object pattern.
- The subject "A perfect dam" is followed by the helping verb "has been" in the present perfect tense and the past participle "built."
- The adverbial phrase "by them across the river" provides additional information about the location and the agent responsible for building the dam.
Option Analysis:
- Option 'A': "Across the river a perfect dam was built." (Passive voice, no mention of the agent responsible for building the dam.)
- Option 'B': "A perfect dam has been built by them across the river." (Correct choice - present perfect tense, passive voice, and includes the agent responsible for building the dam.)
- Option 'C': "A perfect dam should have been built by them." (Incorrect tense - should have been built indicates a past unrealized action, and it does not mention the location.)
- Option 'D': "Across the river was a perfect dam." (Incorrect sentence structure - it does not include the verb "built" and the agent responsible for building the dam.)
Therefore, option 'B' is the correct answer as it accurately represents the tense, voice, and includes the location and the agent responsible for building the dam.