Young people who don't speak "proper" are not as "daft" as they seem, according to research published this week.
In fact, a third of the 11 to 15-year-olds covered by a School Curriculum and Assessment Authority study used Standard English in at least some of their speech, with the girls more likely to use it than the boys.
And the researchers found that children often slipped in and out of Standard and non-Standard English in the same conversation, demonstrating that they used non-Standard words and phrases through choice rather than ignorance.
Professor Richard Hudson and Jasper Holmes of University College London classified 1,456 conversations for a paper published by SCAA.
They found that in a sample drawn primarily from inner-city areas, 32 per cent of the speakers used no non-Standard forms at all.
Also, 16 per cent of the pupils whose conversations they classified alternated between Standard and non-Standard forms of spoken English.
"At least one speaker alternated in this way for each of our non-standard forms except 'me and him went', 'was sat', 'that fast', 'dead good' and 'people who's'," they report.
"These are all quite rare patterns so the gaps are most likely due to lack of data, and it is probably safe to assume that alternation would be found for every non-standard form if we had enough data.
"This alternation is important from an educational point of view because it shows that at least some pupils use non-Standard English forms not out of ignorance but by choice."
They add: "No doubt any increase in the size of the database would tend to move speakers into the alternating category (and would never move them out of it), but of course we cannot go so far as to say that every speaker is capable of using either form. This is presumably a question of fact, but not one that we can answer here," they say.
The database was 2,000 tape recordings of the speech of 350 pupils in Merseyside, London, Tyneside and the South-West made in 1988 by the National Foundation for Educational Research as part of a survey into children's use of language.
Take, for example, these words spoken by two 15-year-old boys from the same school in the South- West: "He shoots them, throws them out the window, takes the fish out of the tank, throws the tank out of the window"; "He takes him out of the room, and he takes the fish out of the tank, he throws the tank out the window as well and he runs out of the door - runs out the room."
The researchers also found that 40 per cent of the girls in the sample used nothing but Standard English compared with only 28 per cent of boys. They say the small sample could be biased but the statistics could also be yet another example of the widespread tendency for females to use more Standard speech than males, reported in numerous socio-linguistic studies.
However, the researchers say that the difference between boys and girls is not as significant as the difference between 11 and 15-year-olds' use or non-use of non-Standard English.
Fewer 15-year-olds than 11-year-olds used spoken Standard English exclusively, but the researchers point out that this difference may be explained by the fact that 15-year-olds spoke for longer and attempted to use more complex constructions.
The most widely used non-Standard forms of English were there is (used instead of there are) in the South-West and Merseyside; ain't in London; and out the window in Tyneside.
Children's Use of Spoken Standard English will be available from May 1 from the School Curriculum and Assessment Authority, Newcombe House, 45 Notting Hill Gate, London W11 3JB, price Pounds 4.