Sentences in the future tense can be said in the passive voice.

The Future Tense

will (do something)
He will steal the car tomorrow

be going to (do something)
They are going to be buying the company.

Passive Voice

The passive voice is:
be (in correct tense) + p.p.

So in the future tense it is:
will be + p.p.
going to be + p.p.

The car will be stolen by him tomorrow
The building is going to be built next year.

Future tense sentences in the passive voice

(active) I will buy that car
(passive) That car will be bought by me

(active) She will kill him
(passive) He will be killed by her

(active) They will finish the housework tomorrow
(passive) The housework will be finished tomorrow

Exercises

1. Change these sentences in the passive voice.
(i) They will be rowing the boat with all their strength.
(ii) Armstrong’s will publish the book.
(iii) We will be giving free speakers with these computers.

2. Change these sentences out of the passive voice.
(i) The exams will be taken on Tuesday.
(ii) Everyone who helped will be rewarded by the management.
(iii) The game will be cancelled by the referee because of the bad weather.