这是进行时的被动语态,结构是be being done.
进行时的结构是be doing,被动语态的基本结构是be done,
进行时的被动语态时,be doing中的"do"就由"be"来代替,合起来就是be being done.
e.g.The flower was being watered.(过去进行时的被动语态)
The car is being repaired.(现在进行时的被动语态)
The book has been being read for one hour.(现在完成进行时的被动语态)