Question

Passive voice of they have posted all the letters yesterday

Answer 1

All the letters have been posted by them yesterday.


Hope it helps...... :)

Answer 2

Answer:

All the letters have been posted by them yesterday.  

Explanation:

1. To keep the tense same. (Very Important)

2. change the place of Subject and Object.

3. Add the helping word. (In this case helping word is HAVE BEEN)