That quote seems quite dangerous—their ‘sure-fire’ way of identifying passives is not sure-fire at all. He is gone is not passive, for instance, and nor is I am confused necessarily.

Ok, I modified the answer to note the exception used with some intransitive verbs that retain older construction forms of English that allowed present perfect with "be" rather than "have". HOWEVER, while these may not technically be passive voice, they are certainly not as active as other choices, as one of my undergrad professors noted to me. For instance, "he is gone" may not technically be passive, but it's not very active either. "He left" is an action. "He is gone" is state, not an action. "I am confused (by it)" is passive - please explain why you would argue it's not.

I am confused by it is passive; I am confused is not necessarily passive. Past participles can and do act as regular adjectives as well as being used in passive constructions.

Perhaps, but your example is passive voice. If you say 'I am confused' then it is implied that there is some cause for the confusion so implied is (by it) or (by something) or (by someone) which means the active sentence is 'something confused me' or similar and your sentence is passive voice. I would need to see a link to some source supporting your position because the sources I checked do not support your argument.

“Don't listen to him, he's always a bit confused” does not imply any agent or cause of the confusion—in fact, it implies that there is no cause, that's just the way he is. “I’m honoured/excited to be here” does not imply that someone or something has honoured or excited me to be here—in fact, the corresponding active “[X] has honoured me to be here” is borderline ungrammatical and definitely means something else than the original sentence. There's a huge grey area between true passiveness and true adjectiveness, which is why I said the blanket statement given in your link is dangerous.

As for a source, I would suggest reading pp. 29–32 of this MA thesis capstone, which deals briefly but exactly (with references) with the grey areas and possible interpretations in the adjective–passive spectrum.

Janus: "He's always a bit confused" still has an agent (by everything). Active voice would be "everything always confuses him a bit." Your latest example "I'm excited to be here" is also passive. Active is "Being here excites me." It does imply something has caused the excitement, namely 'being here'. Your other latest example "I'm honoured to be here" is also passive. Active is "Being here honours me", which is no way ungrammatical. Your example that you say is active voice, "[X] has honoured me to be here" is again passive voice. Active is "[X] honours me by being here."

@Brillig, there is no way for something to be "more active" than something else. Being active voice is a binary condition, either it is active, or it isn't. "I am confused" by itself can absolutely be a copula with a predicate adjective. In fact, the very first example for confused as an adjective in my dictionary uses it in exactly that structure: "she was utterly confused about what had just happened". An adjective cannot be used for a passive structure.

Just because something can be interpreted as either a passive constructure or a copula doesn't mean you must interpret it as one way or another. "I'm happy to be here" is the exact same structure as "I'm honored to be here". It is not passive. It is a copula. There exists no sentence "Being here happies me". To encourage (but not per se obligate) the passive interpretation, you would need to say "I'm honored by being here".

Janus: I opened the MA thesis you linked and it did point to where some researchers have argued ambiguity for examples similar to yours. BUT it should be noted it didn't accept those positions, stating "Take the sentence, 'The child is scared.' In the current study, the word 'scared' is considered as a past participle modifying the child." The study concluded the example sentence is a "short passive". So per this citation "he is confused" would also be a 'short passive' (passive voice). That's what most mainstream sources I have read would also conclude.

guifa, first, refer to Messenger (2009) in the MA thesis capstone Janus Bahs Jacquet quoted above on p.31 for a discussion of "non-actional" versus "actional" as an example of a serious researcher who recognizes there are degrees of activeness and the binary approach doesn't tell the whole story. Even people who stick to active voice/passive voice strict definitions admit there are words which are more or less active than the typical words in those categories.

guifa, second, I think you will find that many past participles begin with adjectives and past participles are a fundamental part of passive voice so your contention that adjectives "cannot be used for a passive structure" is, well, unsupportable. Also, try "being here makes me happy" for the active voice. The 'made' is understood in "I am (made) happy to be here."

Regardless of the semantic interpretation of a clause, morphologically, a verb in English is either active or it isn't. There are some verbs for which they might be morphologically active, but semantically passive "The cake baked in the oven", but that doesn't change the fact that "The cake baked in the oven" is morphologically active (at best you can call it middle voice, but it separate from its morphology).

The paper JBJ cited does an excellent job distinguishing true passive voice from copula + participial adjective. You clearly have misunderstood what she was referring to by (non)actional verbs. That has nothing to do with their voice — only that some children acquire fluency with the passive voice sooner in one subset than in the other. I believe you're confusing the term/idea "action verb" with "active voice".

guifa every statement you make takes you further and further into orbit. Let's see if you can grasp the fundamentals first before addressing any of your increasingly speculative and silly notions. As I previously requested, please defend your comment that "an adjective cannot be used for a passive structure" which you made 7 comments above. Show me. Support that statement. Provide a source. If you can't, then there's no reason to go further. Hint: you can't, and since you don't even understand basics how am you going to rationally discuss nuances?

Source: CGEL. Show me any, any, any document that states that a passive is formed with an adjective and not with a participle. Every single authoritative source will state to the effect of "true passive is formed with an auxiliary verb (be, get, etc) and a participle". They will also state that only transitive verbs (of which be, as a copula, is not) cannot be made passive. These are simple facts of English grammar.

Please, read languagelog.ldc.upenn.edu/nll/?p=2922 and learn what actually is passive voice and the numerous ways to form it. A passive construction requires a participle. If you won't believe Pollum, then frankly, I don't know what to say. He is, after all, the author of the Cambridge Grammar of the English Language. But, prove me wrong. Show me one instance of an adjective (and not an ambiguous case where an adjective and participle share forms) in a passive construction.

guifa I'm still waiting for you to grasp the fundamentals first before addressing any of your increasingly inane and ridiculous notions. As I previously requested, please defend your comment that "an adjective cannot be used for a passive structure." Provide a link and quote the relevant words. You talk in a lot of circles but not one piece of evidence you've provided matches your words which I have quoted. Defend the words you actually said not your revisionist characterizations of them. Maybe in the process you'll learn some of the basics you're lacking.

I said you cannot use an adjective for a passive. That is simply a fact, recognized in every single grammar I have ever seen. By stating passive is made with a participle (which every single grammar does), that necessary indicates that a passive is not made with other parts of speech. I have provided you evidence, you have ignored that evidence. If you'd like to provide a single shrap of evidence of even a poorly written style guide like S&W that indicates an adjective made be used, I'll change my tune. It's simple. Put up or shut up.

guifa if your comment that "an adjective cannot be used for a passive structure" is "simply a fact" as you claim then you should have no problem providing a link and quoting from that link something saying exactly that. Otherwise you are exposed as a fraud. This is your statement not mine, and I have been asking for this same evidence for days now which you can't provide because you are fraud. You put up or shut up.

@Brillig Sorry, but the simple fact that you claim (much higher up) that “[X] has honoured me” is passive just proves beyond reasonable doubt that you just don't know what the passive voice is. That sentence is 100% active voice; there is nothing passive about it.

@guifa has already provided several sources that state quite plainly that a passive in English requires an auxiliary and a participle. Participles may often (usually) also be usable as pure adjectives, but that does not mean you can just willy-nilly change the definition of the passive and say that it's constructed with adjectives, rather than participles. Yellow is an adjective; the sun is yellow is not a passive construction, no matter how much you try to explain it away as one.