Question

change the voice -------- (1)Rome was not built in one day
please it's urgent

Answer 1

The correct change of voice along with explanation of the given sentence  is given below:

This is a subject implied case. A subject implied sentence in active-passive voice is a sentence that is passive but the subject is missing. While converting it into active we have to provide the subject from our side. This sentence is already passive. So we will provide the subject ‘them’ from our side. Hence the active voice of the given sentence will be as given below:

They did not build Rome in one day.

Since the passive sentence is in Simple Past Tense, the active sentence will also be in Simple Past Tense. 

Answer 2

When the voice is changed from active voice to passive voice or vice versa, the subject gets changed to the object and the object gets changed to the subject.

However, in the given sentence, the object has been given but the subject is not given. So, to make it a legible sentence, a new subject should be added.

Usually, the subject is a person. Since the sentence is about work done by people, the subject to be added will be a word that defines people. So, it will be apt to use the word 'They'.

So, the correct sentence after changing the voice will be - 'They did not build Rome in one day'.