They have finished the project. Make it passive -

• The correct passive form is: The project has been finished by them.

- They have finished the project. - এই বাক্যটি present perfect tense এবং assertive sentence -এ আছে।

• Present perfect tense - এ থাকা assertive sentence -এর active voice - কে passive voice করার নিয়ম হলো -
- Active voice- এর object হবে passive voice - এর subject.
- তারপর Tense অনুযায়ী auxiliary verb বসবে এবং মূল verb - এর past participle বসবে।
- তারপর preposition (by, with, to, at, in etc. বসবে).
- এরপর active voice- এর subject টি passive voice - এর object হবে; (objective ফর্ম বসবে).
- এখানে preposition - by যোগে active voice- এর subject ‘They’ - এর objective ফর্ম them বসেছে।

• তাই নিয়ম অনুসারে সঠিক passive form হবে -The project has been finished by them.

- Active: They have finished the project.
- Passive: The project has been finished by them.

Source: A passage to the English Language by S M Zakir Hussain.