Explanation

Note that before a sentence can be passivized, it must fulfil two conditions: the active sentence must contain a transitive verb and there must be at least one object in the expression. Once those conditions are fulfilled, then it is possible to passivize an expression. Also, to passivize an expression, the statement undergoes certain transformation. First, the subject in the active becomes the optional by-agentive adverbial, for instance, "she" turns to "by her". Second, the active object becomes the passive subject. Third, the verb is increased by one, however the state of the verb in the active must be considered too in the passive before inserting verb BE or HAVE.

Note that before a sentence can be passivized, it must fulfil two conditions: the active sentence must contain a transitive verb and there must be at least one object in the expression. Once those conditions are fulfilled, then it is possible to passivize an expression. Also, to passivize an expression, the statement undergoes certain transformation. First, the subject in the active becomes the optional by-agentive adverbial, for instance, "she" turns to "by her". Second, the active object becomes the passive subject. Third, the verb is increased by one, however the state of the verb in the active must be considered too in the passive before inserting verb BE or HAVE.