Teachers who were not taught grammar at school are struggling to teach it today, according to a government-commissioned study.
The major review of research on how best to teach secondary pupils to write complex English has revealed evidence that their education is suffering because of some teachers' "limited confidence with grammatical terms".
"For English teachers, who themselves attended schools when grammar was not part of the English curriculum, there is a significant issue of lack of assurance in grammatical subject knowledge, leading to difficulties in addressing grammar meaningfully," the report from Exeter University said.
Research into trainee teachers' subject knowledge showed that they "may not have enough understanding of the writing process themselves to teach it effectively".
Academics report that the pressure of high stakes testing and league tables can force teachers to "reduce writing to a formula, stripping it of meaning and purpose".
"There is research evidence to suggest that in order to secure development in pupils' writing, there is a need to 'skill up' teachers in terms both of their subject knowledge and their understanding of effective teaching strategies," they said.
John Bangs, head of education at the National Union of Teachers (NUT), said teachers should be surveyed to see what on-the-job training they needed to help them fill in gaps. "I think there is an issue about understanding grammar," he said. "The danger is that this will be seen as teachers' fault when it isn't."
Mr Bangs said staff who went through teacher training colleges in the 1970s and 1980s were most likely to be affected.
He said the teacher literacy tests introduced in 2001 were too narrow to make a difference, but that the training carried out following the introduction of the national literacy strategy would have helped.
One study the Exeter Universtity team examined found trainee teachers were more concerned with the terminology of grammar, such as nouns and verbs, than the actual role the words played in a sentence.
Solutions suggested by the report include using real texts to analyse how punctuation was used and teaching that it is a "rhetorical tool used for effect, rather than bound by fixed rules".
The Exeter study also recommends giving pupils a choice of writing topic, within a framework such as a "five paragraph theme" to promote more creative choices of words and sentences.
'Effective Ways of Teaching Complex Expression in Writing' is at www.dfes.gov.ukresearch.