ANSWER :
✠ Active Voice :-
➨ The authorities have sanctioned the plan.
✠ Passive Voice :-
➨ The plan has been sanctioned by the authorities.
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NOTE :
✎ The given sentence of Active Voice is in Present Perfect Tense.
✎ Sentence Structure of Present Perfect Tense in Active Voice :-
★ Subject + Have/Has + Past Participle form of Verb + Object
✎ Sentence Structure of Present Perfect Tense in Passive Voice :-
★ Subject + Have/ Has + Been + Past Participle form of Verb + Preposition + Object
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MORE TO KNOW :
❖ Voice :-
➯ In English grammar, Voice refers to a form of verb which shows whether what is denoted by the subject does something or has something done to it.
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❖ Types of Voice :-
[1] Active Voice.
[2] Passive Voice.
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❖ Active Voice :-
➯ Active Voice refers to the voice that a sentence has a subject which acts upon its verb.
➯ In Active Voice, the subject is the doer of the action. The subject may be a person or a thing who does something. The verb in Active Voice shows the action of the subject.
➯ Active Voice is so called because the subject of a sentence of Active Voice perform/ does/acts upon the action shows by the verb.
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❖ Passive Voice :-
➯ Passive Voice refers to the voice that the subject of a sentence is a recipient of the action of the verb.
➯ Passive Voice represents a sentence where the subject of the sentence receives the action, performed by the verb, i.e., the verb's action is done or performed by the subject.
➯ Passive Voice is so called because the subject of a sentence of Passive Voice suffers/receives the action of verb instead of directly acting upon the verb's action