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The Magazine's recent piece on uptalk - the habit of making statements sound like questions - prompted lots of you to email theories of where it started. Here are 10 of the most popular.

From Japan to Bristol, the Valley girls to Neighbours, theories on uptalk are far-ranging. Here are some readers' ideas, with comments from four linguists who look at its usage.

1. It started in Scandinavia

Johann, Reykjavik, Iceland: "Norwegian is the mother of all uplifting inflection languages. Whether a question or a statement, Norwegians always end on a higher note."

John Kouhia, Kirkkonummi, Finland: "I have always been puzzled by the prevalence of uptalk in Norwegian. Everybody uses it a lot. It seems to be used in most sentences especially in the last sentence that finishes presenting an idea or concept. I often wonder if they are asking for agreement on what was just said."

Aardman, Minnesota: "I live in Minnesota and people have been uptalking here well before California made it famous. It's from all those Scandinavians who settled here. Go watch Fargo. The intonation is exaggerated but more or less accurate."

Image copyright Getty Images Image caption Did it come over with the Vikings?

Professor David Crystal, an honorary fellow of the Chartered Institute of Linguists, says: "This is a very credible theory. Uptalk dates back to the Danish in Anglo Saxon times. No one knows exactly where it started but all you can do is listen to how Danish and Scandinavian people speak. They certainly have that inflection."

2. It's a lack of confidence

Vernon Pilgrim, Tokyo, Japan: "I think it's insecurity, constantly reaching for confirmation."

Andreas Stradis, London, UK: "A considered statement, it seems, cannot now be made without due consideration of its liability to be questioned, as if to say, 'I anticipate your boredom and your misgivings, but if you suspend your disbelief for just a moment and let me get to my point, may I leave you to corroborate my story on your iPhone after it has been made?'"

Brian Turner, Spain: "Our two-year-old granddaughter chatters away, but finishes each sentence on a high rise. I believe she is asking "did I say it right?" That may also be a source of it in adults."

Rob Drummond, a lecturer in linguistics at Manchester Metropolitan University: "A lot of people think it's a sign of insecurity and being unsure, but I think it's misunderstood. It's used in such a variety of ways, yes it can be that, but it can also be used quite aggressively and in a dominating way."

3. It's Japanese

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Mac McMurran, San Juan Capistrano, USA: "I first ran into it in Japan and Korea in 1952/3, where we were influenced by the Japanese -ne? used often at the end of declarative sentences. I always thought it was used as a polite softening of an assertion, and looking for at least tacit agreement."

Vernon Pilgrim, Tokyo, Japan: "The Japanese have a similar habit, except that it involves lots of quick nodding of the head as if to reassure him - or herself - that the listener is agreeing. Japanese being a harmonious people, this nodding for agreement and reassurance is necessary, the nodding goes on even after the sentence has ended."

Vivian Cook, a professor of applied linguistics at Newcastle University, says: "The Japanese have a different kind of intonation system to English, tone is used in a different way. People may have heard uptalk used but I think it would have a different meaning or reason."

4. It's from Neighbours

RJS, Winchester, UK: "For a couple of years in the late 80s Neighbours was watched by in excess of 15 million viewers five evenings per week, with Home & Away not too far behind. It might explain how uptalking spread throughout the UK."

Anthony Bretherton, Epsom, UK: "The upward inflection was, I feel sure, first used by young people when Kylie Minogue and Jason Donovan were popular young stars in Neighbours in the 80s."

Craig Hammans: "Aussies are pioneers in this field. Stephen Fry describes it as Australian Questionitis."

Crystal: "It is important to know that there isn't anything particularly 21st Century about uptalk. It goes back to the start of language."

5. It's from New Zealand

Mark Webster, Auckland New Zealand: "The rising inflection, as it's called here, has been a much talked about feature of New Zealand speech for as long as I can remember (that's back to 1965). But lots of Scots settled here, and cities like Dunedin still have loads of people with Scottish surnames."

Mark Annand, Kathmandu, Nepal: "The high rising terminal has long featured in speech in New Zealand. In my own experience it was common among semi-fluent Maori speakers in the 1950s often used in the form of a statement ending with ...eh?"

Image copyright Getty Images

Mark Liberman, a linguistics professor at the University of Pennsylvania, says: "All varieties of English can use final rises as 'queclarative' - to ask a question in statement form - as requests for confirmation or response. What happens in some varieties is that final rises are used by default. The uptalkers in Australia, New Zealand, and the US seem to have reached this same state."

6. It's Celtic

Bobby Downey: "In Northern Ireland we go high to low and back to high, so we do."

Elizabeth Isaac, Panama City, USA: "I first came across this peculiarity of speech 33 years ago, when my boyfriend, now husband, took me to meet his family in South Wales. The family is from Barry, but my mother-in-law was born in the Welsh mining village, Abertillery. I thought it a bit strange at the time, but just accepted it was part of the sing song lilt of the southern Welsh."

Image copyright Getty Images

Cook: "It's certainly common in the Belfast accent. It's very Celtic, I think this is quite a common theory." Lieberman adds: "About 20 years ago, a Canadian student of mine recorded a few hour of sports talk radio from Toronto - in it the older men commonly used final rises. From what little I know of Canadian immigration patterns, Scots-Irish influence seems plausible."

7. It's a sales voice

Richard Ely, Alfreton, UK: "I was introduced to uptalk as a sales technique - finish your sentence on a rising inflection and add a 'yes' at the end and people will be more likely to agree with you."

Image copyright Getty Images

Crystal: "Uptalk can encourage rapport and it saves time. People will usually answer with a nod or a question. I can see why sales people would use it, but it's not where it started, uptalk has been in language ever since language started."

8. It's French

Martha: "I'd suggest that uptalk began as a shortened form of asking for agreement, similar to the French ending a sentence with 'non?', a Canadian with 'eh?', or an American with 'OK?'"

Jeanne, US: "I have always heard an upward lilt to speech and assumed it was from my Quebec, French-speaking relatives when they switched to English. I spent many years there as a child and picked up the cadence in their speech."

Liberman: "There are many language varieties around the world that use... final rising intonations. This is true of French, for example... and in Malayalam, a Dravidian language of South India. Final rises on non-paragraph-final phrases are normal in French. But it seems unlikely that this has anything to do with the final rises in urban northern British or Scots or Belfast English, any more than the rising accents in Malayalam are connected to either of them."

Image copyright Thinkstock

9. It really is from the American Valley Girls

Elizabeth Parker: "Most of the kids I taught for the past year (in a landlocked rural West Midlands county with a perfectly acceptable accent of its own) tried to talk like this. It irritated the proverbial out of me. Not to mention the likes of 'Miss, where's the aluminUm?' and 'X, Y, Zee...' Grrrr! Even the some of the boys tried to sound like (San Fernando) Valley Girls at times."

Martha: "I've always thought of it as a Valley girl mannerism, but, then, I live in Oregon. Interaction between young girls often is very collaborative in nature. I've noticed that young people here order in restaurants with the question structure: 'Can I have a hamburger?' (upward inflection), rather than a statement: 'I'll have a hamburger.' I suppose it is an effort to seem polite without adding 'please'."

Cook: "I remember in the 1940s and 50s hearing it a lot in American films, it was used a lot in Hollywood at the time I think. It was linked to the American 'southern drawl', as it was called."

10. It's Bristolian

KLS Dennis: "In the 1950s and 60s, I spent a lot of time with cousins from Bristol whose dialectic intonation was so strong, it took relentless concentration on my part to understand them. My 'home counties' speech amused them too. While their dialect was strong, their grammar was sound and they were sufficiently aware of their intonation to refer to it as the 'risin' Brizzol intonation'. They explained that it was commonly assumed to have begun with the late 18th Century Bristolian sailors, who, aware of the strength and complexity of their dialect when talking to folk abroad, or even in other parts of Britain, turned every statement into a question to ensure the listener was keeping up - a very important tactic for successful bartering."

Drummond: "This is a really nice theory, and it makes sense - it could certainly explain why it is part of the Bristol accent. I don't think Bristol is where the upward inflection started, that's something no one knows, but it's a nice reason for it being in that part of the country."

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