2 ways of using Passive Voice?

Question

I'm trying to understand how to use the passive voice and so far I've come across 2 ways that it's been said : using ser/estar + adjective or se + (third person verb). The thing is, I don't understand wether you can use both of them to mean the same thing or not. For example, "the book was written". Could it be written these two ways or not:

El libro fue escrito

se escribió el libro

If you can't write them in these two ways, can you please explain why and when to use the different ways? Thanks!

Answer 1

In Spanish, the passive is only constructed by using the correct form of the verb ser + past participle. The use of estar + past participle is not a passive construction. Instead, the past participle in that case works as an adjective.

1. La puerta está abierta. (= condition of being open)
2. La puerta es abierta todos los días. (= present passive indicating a permanent situation)

The other way to use the passive is by using the reflexive passive. This happens when you use se:

1. Los libros son vendidos rápidamente.
2. Los libros se venden rápidamente.

Reflexive passive only works when the verb is transitive and the agent is never mentioned. (Because it's an impersonal construction.)

Answer 2

From what I've learnt your two example sentences are correct and interchangeable. But with your description, I think you can only use "ser" with the passive construction, not "estar." Using "estar" would change the meaning. For example:

La puerta fue abierta - The door was opened (by some agent)

La puerta estaba abierta - The door was open (that was the state of the door)

I'm pretty sure that's right, but I am only a learner so stand to be corrected