@Brus - OK, here's my suggestion - it's not a passive, it's not an incorrect past progressive, it's an adjectival participle, as in:

"The house is situated between two large oak trees"
"There were two vases of flowers placed in the middle of the table"
"She's a bit run down at the moment"
"I'm done with the photocopier if you need it" (colloquial but standard - done is an adjective here)

Better still, just treat it as an idiom, or a colloquialism, which is perfectly OK to use in informal (normal) contexts. And one that is increasing in use amongst speakers of otherwise absolutely standard British English, and not only Northerners. According to Ngram its use has tripled in British books in the last two decades or so. A few more years and I don't suppose anyone will bat an eyelid. Actually, in Britain, I think that's pretty well true already, apart from a few pedants.

http://books.google.com/ngrams/graph?content=he+was+sat%2Che+was+stood&year_start=1990&year_end=2008&corpus=18&smoothing=3&share=

@Tessa Avon - while I sympathise with your main drift (and it probably does sound better coming from someone like Lee Mack), I'm not sure about your last point - "He was sat sitting at the table". Doesn't sound quite right to me.

@Justice Jim - sorry! But I think the "pled" "pleaded" thing did get pretty well discussed before we got diverted. There aren't many of these threads that go "into the grey".

@Brus - Words change, this is from Oxford Dictionaries Online, for 'demographic' (not 'demographics'), and it means more than just class or race:

"noun - a particular sector of a population - the drink is popular with a young demographic"

You may see it as coy, but it is also efficient: one word where several would have been needed otherwise, and nearly everyone knows what it means. Actually, the bit about it being more common in the US was really only my intuition, but it seems to borne out by this:

http://books.google.com/ngrams/graph?content=demographic_NOUN%3Aeng_us_2012%2Cdemographic_NOUN%3Aeng_gb_2012&year_start=1960&year_end=2000&corpus=15&smoothing=3&share=

But my real problem is that you should take it on yourself to baldly criticise Zee's choice of words, especially when it is quite a normal word in the circumstances. The way I was brought up, that's simply bad manners.

@Skeeter Lewis - for example I've just heard an announcer on BBC Radio 4, with an otherwise standard "middle class" accent pronounce "past" with a short a - /pæst/ rather than a long a - /pɑ:st/.

Inkhorn terms - for anyone interested, there is also quite a lengthy discussion in "Early Modern English", by Charles Laurence Barber, much of which is available at Google: http://books.google.pl/books?id=Iat4Bk_YeR4C&pg=PA56

@Warsaw Will - "While many if not most of the inkhorn terms you so despise are still with us, few of the "English" substitutes have survived." OK, I probably overstated the first part, although I stick by the second. I listed "agile" etc as Inkhorn terms, because they are listed as such at a couple of US academic sites, such as Rhode Island College and Towson University.

I accept that we are better off without many, perhaps most, of the words Thomas Wilson lists in his "An ynkehorne letter". But on the other hand, that letter also included "ingenious, capacity, mundane, celebrate, extol, dexterity, illustrate, superiority, fertile, contemplate, invigilate, pastoral, confidence, compendious, relinquish, frivolous, verbosity", only two of which "compendious" and "verbosity" would I baulk at using (in the right context).

Of those "nativist" words put forward by Ralph Lever (eg witcraft for logic, endsay for conclusion, foresay for premise), few have survived. And as Micheal Quinlon at World Wide Words says "Whatever the reason for success or failure of new words, this extraordinary period of inventiveness and adaptation enriched English with many hundreds of new terms."

Later purist writers don't seem to have been any more successful in persuading us to use their "simpler" equivalents, whether Nathaniel Fairfax (1674) - (eg bodiless for immaterial, middlekin for medium, thingsomeness for reality’) or William Barnes (starlore for astronomy and speechcraft for grammar). Although I accept that Barnes' poetry has a lot of merit, his invented words didn't really catch on.

http://www.ric.edu/faculty/rpotter/inkhorn.html
http://www.english.illinois.edu/-people-/faculty/debaron/403/403%20emne/inkhorn.html
http://www.worldwidewords.org/articles/inkhorn.htm

"After moving from Chicago down to northeastern Georgia, I have noticed an extremely vexing trend among many of the native Southerners" - it really is so vexing when other people don't speak like we do, isn't it? For example, Americans have this strange habit of saying "on weekends", when everyone knows "at weekends" is the correct version. And what's this with "outside of" and "off of" when "outside" and "off" are perfectly good on their own?

I'm being ironic of course. My point is that although you might find somebody else's English strange and illogical, someone somewhere will probably find elements of your English just as strange and illogical. Does it really make all that difference to your life that some people say "on tomorrow", whether it's an ethnic thing, a regional thing, or a fashion thing?

There seems to be an unfortunate element on this and other PITE pages of looking down on people who speak differently from you. It might not come under the banner of racism (although ebonics seems to get mentioned rather a lot), but it's certainly snobbery. In the last few days we've all seen the example of somebody (in Cleveland) who talks a bit "differently" but who is a real hero. Just because people "talk proper" in no way makes them superior to those who don't, just "posher". They just speak the dialect which has more social cachet, that's all. And if they make an issue of it, I'd say quite the opposite. Similarly, when they accuse other people of being 'ignorant' or 'lazy', it is their own ignorance of language structure and historical development they are showing. As somebody once said - "a language is just a dialect with an army and a navy".

@brus - I don't really see why you think the use of "demographic" is weird. Its use is not uncommon, especially in the States:

"And in this case, it seems, the commanding officer of a precinct is suggesting an entire demographic be placed under suspicion"- NYT

"If Google+ wants to be the next Facebook, it has to capture the key demographic that drove Facebook's early ... - CNN

"America edging toward demographic cliff?" - Fox News

"Marketers' Dream Demographic: The Smartphone Mom" - Time

"Why the Apple Demographic Is So Important to Orbitz and Retailers" - WSJ

And did your little Scottish girl really pronounce arse with a hard S?

@Skeeter Lewis and others - I agree with you that there is an element of class to it, but I think it's a little more complicated than that, as peteskully pointed out. There's also a regional difference. Yes RP speakers will say /ɑ:nt/ ('ahnt') everywhere in Britain, but I suspect middle middle class northerners are just as likely to say /ænt/ ('ant') as their working class counterparts. Similarly a Cockney will say /ɑ:nt/ ('ahnt') not /ænt/ ('ant'). It's the same with words like 'bath'.

@jayles
First and foremost language is about communication. No, we don't all have to use exactly the same words or word combinations, but if you use other words they need to be understandable. Now, for example, I still don't know exactly what you mean by "wordstring" - phrase, collocation, chunking, and now you say 'coining new words'? And as I wrote Javascript code, I'm perfectly well aware of its programming sense. You seem to think that because I know the component parts I should understand, as in your "requicken", but I don't know what you mean by that either, and I really don't see why I should spend extra effort trying to work out the meanings of words which are just as (if not more) obscure to me as long Latinates. At least I can look Latinates up in a dictionary.

I also think it doesn't show a lot of respect to your fellow speakers to use words they are not likely to understand, for what really comes down to ideological reasons. What other reasons could there be that you feel the need to invent or retool these strange words? Language is a democracy, and certain natural word partnerships have grown up, for example, I might 'quicken my pace', but 'speed up a process'. These natural associations are the basis of corpus linguistics and natural language processing.

Incidentally, "quicken" comes in at 30,926 at Wordcount.org which is based on the British National Corpus. The Wiktionary tables (which I didn't know about and will have to investigate; thanks for that) seem to be based on Project Gutenberg, so are probably a bit more 'literary', not to mention that most books at PG are out of copyright, so more than seventy years old.

http://www.wordcount.org/main.php

Talking of collocations, I have a little compromise to suggest for lunar eclipse - eclipse of the moon. It's not as common as lunar eclipse, but more so than moon eclipse. Although purists will still have the problem of 'eclipse'. Here are some figures for 'lunar eclipse', 'moon eclipse' and 'eclipse of the moon' respectively:

The Guardian - 511, 7, 58
The BBC - 556, 154 , 193
The British National Corpus - 4, 0, 2
Google Books - 145,000, 18,100, 128,000

And here are a couple of my favourite collocation finders -
http://www.netspeak.org/#query=%253F+eclipse
http://www.just-the-word.com/main.pl?word=lunar&combinations=combinations&cdb=thesaurus

Multi-word verb - OK. I hate this term. Why? Because we had a perfectly good system of phrasal verbs divided into four types, which was relatively easy (at least for teachers) to understand. What's more, dictionaries refer to phrasal verbs, there are masses of books on phrasal verbs, but the trendies seem to think that multi-word or multi-part verbs (they can't even make up their minds) are better. If they'd used different names for the four categories (as Wikipedia does), it might not have been so bad. But under the multi-whatever label, only the first two categories are now phrasal verbs, the third being prepositional verbs, and the fourth phrasal-prepositional verbs. Which is bad enough, but nobody seems totally clear as to what verbs the category prepositional verbs includes. I wrote (ranted) about this last year -
http://random-idea-english.blogspot.com/2011/05/when-is-phrasal-verb-not-phrasal-verb.html

I'm not sure I really get your point about present perfect continuous - do you perhaps mean it's literally a multi word verb, because it consists of several words? It certainly isn't technically a multi-word verb, as it has no particle(s).

But as for the prefix "multi-", it is so common, as are other Latin and Greek prefixes, that it shouldn't be that difficult for students to grasp the meaning once they've come across it once or twice. In any case, "many" is just as foreign for them as "multi".

I also far prefer the term "sister company", but I think you overstate the problem, as the students are likely to have learnt the term "subsidiary" well before they come across the relationship between two subsidiaries. In any case, 'sister company' is by far the more common term - 100:1 on Google, 10:1 on Bloomberg, 300:1 at the FT.

Do you really think only people who studied Latin know that "capital" comes from "head"? I would imagine most native speakers know the difference between "capital punishment" and "corporal punishment". And in any case, while knowing about roots is a fascinating subject, it's hardly necessary for understanding the meaning, is it? You rather proved that with "refer, infer" etc example.

There may be a few people who think long words sound "more intelligent", but I imagine most people judge words on their sound and familiarity, not their derivation. I really think that we have to distinguish between the desire for plain English, which I largely go along with, and language purism based on derivation, which is something completely different.

You say - "It seems to me that in this discussion we need to find some common basis for our criteria, otherwise agreement is impossible.". But there is a possible basis. It's called common sense, and using the everyday English that the vast majority of speakers use, and which sounds natural to the vast majority of native speakers. It's the language used by many (but, unfortunately, not all) the commenters at Pain in the English. You won't please the pedants or the purists, but they are tiny minorities who will never be pleased anyway.