Question

we have already done the exercise change the voice​

Answer 1

Answer:

The exercise has been already done by us.

Answer 2

Answer :

The exercise has already been done by us.

Extra Information :

When changing the voice from active to passive, at first the subject, object, and verb of a sentence must be identified. Then, the tense of the verb must be noted, because to transform the voice from active to passive, the necessary form of helping verb should be used. It is succeeded by the past participle form of the main verb.

The given sentence is in present perfect tense and we know that the passive voice form in the present perfect tense is made by putting have/has + been before the past participle form of the main verb.