This question already has an answer here:
I find the standard examples of active and passive voice on, say, Purdue Owl to be pretty obvious. For example, "He kicked the ball" versus "The ball was kicked by him."
For the examples, Someone was talking about whether these different sentences were passive or active voice during a story critique. But when you have "Her hair was dark" vs "She had dark hair." It doesn't seem that either of these would be passive voice. "Her hair was dark" is passive voice? because in passive voice the subject should be receiving the action of the sentence, but that doesn't look to be the case here—her hair is simply dark and only an auxiliary verb is present.
Also, someone was saying "she looked young" is passive, but "she was young" is not passive. But this makes no sense to me. Are they perhaps meaning one is less precise, and they weren't talking about passive/active voice at all when they were saying it was passive? Because all I'm seeing that's different about these two phrases is a narrator that is either uncertain or certain about the subject's age.