You've asked a good question, Leith. I can see why you're asking this, and I can also see why the two native speakers who responded both said it was incorrect. Here's the thing: In theory, it is actually correct: there is no grammatical/structural reason why you can't say "The room has been being cleaned". However, in reality, this structure does not exist. As you pointed out in your comment below '.....the present perfect continuous cannot be changed into passive voice'. This is because it's just too complex and cumbersome to use. If you want to refer to the result, you could, of course, use the simple aspect and say 'The room has been cleaned'. This is a present perfect passive ( not 'past tense', as I'm sure you know). However, if you really wanted to focus on the activity by using a present perfect continuous, you'd find some way to avoid the passive. A typical workaround would be 'They've been cleaning the room'. The vague and impersonal 'they' avoids mentioning who has been doing the cleaning and also sidesteps the awkward passive construction. I hope that helps.

Thats good, it is almost correct :) The room has been cleaned (past - it has already been done) Or The room is being cleaned. (present - it is happening at this moment) If you need any more help with English, feel free to check out my profile. I would be happy to help you improving your English! :)

Hello Leith, I think that it is also possible that you are talking about an ongoing action that happened in the past. (Imperfect past tense) - The room was being cleaned. (It WAS happening in the past, but without start or end.) Example: We were in the room for a long time. While we were in the room, it was being cleaned. Could this be what you were trying to say? Leaening English verbs .. no fun!

Incorrect. Present Tense: The room is currently being cleaned. Past Tense: The room has been cleaned.