This must have been asked before, mustn't it?

Post date: 2018-01-10 15:52:11
Views: 49
The use of the term "mustn't" seems really weird if you think about it, yet it is used regularly. How did this term come to be? What does it actually mean in literal terms?

This question arises from conversation I had the other day, which I finished with "I must have, mustn't I?". A minute later I found myself wondering how on earth such a phrase came to be standard, as the expanded "I must have, must not I?" sounds both ridiculous and non-sensical. So what are we saying when we use this and how did it come to be?

I have googled this but most of what I have found concerns what is correct standard usage and what is not. I understand how to use this phrase, I don't understand what I'm actually saying in a literal sense though. Some of the answers are on linguistic forums and I struggle to follow such answers when they get technical, as with many English speakers I wasn't really taught grammar or linguistics. Also, I believe this may not be generally used in North America, trust me when I say it's correct and standard here.
From: http://ask.metafilter.com/317757/This-must-have-been-asked-before-mustnt-it
 
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