Present continuous passive and past continuous passive

 PRESENT CONTINOUS PASSIVE

Structure: AM/IS/ARE + BEING + PAST PARTICIPLE (+BY+NOUM)

Ex. The computer is being repaired.

http://www.ego4u.com/en/cram-up/grammar/passive/exercises?present-progressive

PAST CONTINOUS PASSIVE

Structure: WERE/WAS + BEING + PAST PARTICIPLE (+BY+NOUM)

Ex. The computer was being repaired.

http://www.ego4u.com/en/cram-up/grammar/passive/exercises?past-progressive