The important points to remember when you want to compare the true passive and the stative passive constructions are the following:
1. In true passive constructions
a. An action is carried out on the subject of the sentence.
b. There is an agent, either expressed or unexpressed.
c. There exists an active voice counterpart.
2. In stative passive constructions
a. The state or condition of the subject of the sentence is described.
b. There is no agent.
c. There is no active voice counterpart.
Not all true passive voice constructions have stative passive counterparts, but many, many do. As teachers involved in the instruction of deaf individuals, it is important that you perceive the distinction between these two identical-looking constructions. In that way, you can intervene more successfully if a student has difficulty interpreting them.