Question

They proposed to hold a meeting

Answer 1

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It was proposed by them to hold a meeting.

Explanation ↴

The given sentence is a simple structure of simple sentence in active voice. When we are going to change the sentence into passive voice, we must take care about the passive structure because double passive should be avoided in simple sentences, as they are liable to give a wrong meaning.

Answer 2

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It was proposed by them to hold the meeting.