Tenses

OK

Sorry if it sounded harsh Tanit... I didn't mean to!

The point I was trying to make is that when people learn English they are given a lot of 'rules' which are actually not true!

I do not adhere to Pedagogical Grammar done in this way as although it may help the teacher get through a class today, it doesn't help the learner tomorrow...

I've seen too many students fail to progress beyond the 'intermediate plateau' mainly because they cannot 'unlearn' the 'wrong rules' they were given at lower levels...

I see no use in 'lying' to students, unlike many coursebook writers, as it only leads to confusion at later stages in the journey to understanding English.

The 'Four Conditional' myth is one of them. In fact many grammarians have moved away from this, and now argue that there are only 'two main divisions' - Real and Unreal, which in themselves have multiple grammatical forms.

It's ironic that things often classed as 'errors' or 'wrong' by coursebooks at elementary/intermediate level are fully acceptable after that stage...

Haven't you noticed that for every 'rule' you are given in English there seems to be a multitude of exceptions? Maybe, it is the 'rule' that is wrong in the first place...

Thank you all for answering my post.

The problem I see is NOT the contrast beween rules and exceptions, or between grammar and spoken language, BUT, basically, the lack of unanimity on what is correct and what is wrong.

After Marius' and Tam's examples, it was pretty clear that the structure debated here:

if + Past Simple (in the past), would + Past Perfect (consequence in the past)

is actually used. Here is what I asked:

Tanit wrote:

(...) I can't still understand if it's grammatically correct or if it's a substandard, but idiomatic and colloquially acceptable, mixed conditional.

Shouldn't I be confused by the answers? MM said that the sentence is 'misconstructed,' you wrote:

J Lewis wrote:

If you were there you would have laughed is an "incorrect" mixed conditional because both parts refer to the past.

but other native speakers, possibly teachers, don't see anything wrong in the sentence, and they simply didn't answer my question. Instead, they focused on explaining general failures in grammar books, teaching methods, simplification of the rules, etc. (which could be right, but doesn't answer).

Rebus sic stantibus, I'll assume that: (i) there's a certain number of people who would use this structure even when the if-clause is a condition in the past, (ii) native speakers definitely don't agree on whether the sentence is grammatically correct, and, as a consequence (iii) I'll try to avoid it both in spoken and in written English, unless the if-clause refers to the present or is always true.

You know, just to be on the safe side ... 

Hi Tanit,

The problem here lies inevitably with the problem of whether or not English Grammar is Prescriptive or Descriptive?

Generally modern English Grammars for native speakers , such as Longman's Grammar of Spoken and Written English (1999), are descriptive and reflect how English is used at 'present'.

From these Descriptive Grammars coursebook writers and Pedagogical Grammar Book writers try to simplified and codify these descriptions into Prescriptive 'Rules'. Herein lies the major problem - they are not so much rules as guidelines. They are not absolutes.

Probably the only native-speakers that believe they are, are newly trained or qualified teachers who aren't sure of aspects of Grammar - I don't think I'm giving away any trade secrets when I say that many newly qualified teachers are usually only a couple of pages ahead of their students when it comes to the 'grammar' on their course. The problem is many schools put newly qualified teachers onto lower levels as their grammar may not be up to dealing with complicated questions of grammar and/or usage.

Unfortunately this coincides with many of these 'guidelines' being misinterpreted as 'rules'. Look closely and you will never see a grammar 'rule' that begins "x is ALWAYS used..." You're most likely to see wording such as: "x is usually/often/generally used..."

The reason being that the Grammar upon which it was based was descriptive, and as such can/could change or that their may be alternatives that are not included (at that moment)...

English isn't a 'dead' language and so aspects of usage are constantly changing and often vary from person to person in level of acceptability. Herein lies the problem as exemplified by this thread; native speakers have different reference points as to what is 'correct'. Is it what they were taught at school themselves? Or what they hear and see around them now? What Michael Swan says? Or Murphy? Or their coursebook?

English is an inclusive language in which many things are possible, and usually are! However, although many constructions are possible, you will hear different native-speaker teachers argue about this based upon their personal experience.

The problem is that native speakers use constructions or collocations which are not easy to teach, or are as yet unmapped or unrecorded as far as reference tomes are concerned...

Take this example:

"The copyright on sound voice recordings may be expanded from 50 years to 95 years."

Sounds like an error? Shouldn't it be "...may be extended from 50 to 95 years" as it's about a time period?

If you were a non-native-speaker, most teachers would probably tell you that you have made an error to use 'expanded' here as it should be 'extended' or 'increased' or something similar...

Only this was from last Sunday's BBC Radio 4's podcast of 'Broadcasting House', and said by the 'educated' native-speaker presenter...

So? Is it still a wrong collocation? I mean... if you can't trust the BBC, who can you trust?

Hope that helps...

Marius,
knew is not in the if-clause in the Rowling example.
It's the backshift of They know that if they retaliate they will get detention.
Are you sure that's the right example here?
Don't you need They knew that if they retaliated they would have got detention to get the mixed conditional idea?
I'm a little late to enter this thread, but just from the material in the quote box I wasn't able to see the connection. 
Jim