My textbook just taught me about っぱなし and how it indicates that X wasn't followed by Y as it is usually expected. It also taught me that this expresses that this fact is perceived negatively by the speaker.
What it didn't explicitely teach me is how it functions syntactically ^^ So far, I noticed that it is only used in this way:
Subject + が + verbっぱなし
Example: あの家は留守らしい。洗濯物が4,5日前から干しっぱなしだ。
This pattern even extended into sentences like this one: 1週間前から階段の前にバイクが置きっぱなしにしてある。
where the verb in use 置く confuses me a bit since I only encountered it in the pattern
subject + を + 置く
In addition, whatever rules the things coming AFTER っぱなし follow is still kind of a mystery for me. I frequently see っぱなし being followed by the copula as in my first example.
However sometimes it is also followed by something like in example 2. I would guess now that っぱなし is a noun? In this case, from a grammatical point of view, both the copula and the example 2 case would be viable I guess? If it should be the case that っぱなし is a noun I would expect a fixed set of particles being required for constructions like in example2 since the
verb+っぱなし
complex feels like in the function of an attribute or adverb here, and therefore I'd usually expect something like の or に.
