This is off the
internet too, Abmateen, but I could do no better:
Personal Passive simply means that the object of the active
sentence becomes the subject of the passive sentence. So every verb
that needs an object (transitive verb) can form a personal passive.
Example: They build houses. – Houses are built.
Verbs
without an object (intransitive verb) normally cannot form a personal
passive sentence (as there is no object that can become the subject of
the passive sentence). If you want to use an intransitive verb in
passive voice, you need an impersonal construction – therefore this
passive is called Impersonal Passive.
Example: he says – it is said
Impersonal Passive is not as common in English as in some other languages (e.g. German, Latin). In English, Impersonal Passive is only possible with verbs of perception (e. g. say, think, know).
Example: They say that women live longer than men. – It is said that women live longer than men.
Although Impersonal Passive is possible here, Personal Passive is more common.
Example: They say that women live longer than men. – Women are said to live longer than men.
[To form Impersonal Passive] the
subject of the subordinate clause (women) goes to the beginning of the
sentence; the verb of perception is put into passive voice. The rest of
the sentence is added using an infinitive construction with 'to'
(certain auxiliary verbs and that are dropped).
Sometimes the term Personal Passive is used in English lessons if the indirect object of an active sentence is to become the subject of the passive sentence.