Is it necessary to have agent while constructing Perfect tense?. I mean some activities are spontaneous like Fallen, grow up, increased, expired etc.
Tree has been fallen. Water level has been increased. My account has been expired.
Some more examples
Villages around the area have been cut off from the outside world, Visave said. Nearly 50 villages in the district have been cut-off from the tehsil headquarters and two bridges remained submerged as heavy rain continued to lash Thane on Wednesday.