Sarah Churchwell: Why can't British students write like Americans?

Every spring, I have Rex Harrison's voice in my head, singing: "Why can't the English teach their children how to speak? Norwegians learn Norwegian; the Greeks are taught their Greek." For eight years I've been teaching extremely bright, overwhelmingly middle-class university students studying American and English literature, who achieved minimum A-level scores of three Bs. They are intelligent, skilled at passing exams, and most of them don't know what defines a complete sentence. This is not sarcasm: every year I ask my students to name the three parts of a complete sentence. Usually they mumble, "subject, verb, object" or "subject, verb, predicate". I have never had an English student who knew the answer. The Norwegians and the Greeks do. So do the Americans, because they were taught grammar, vocabulary, and spelling. The majority of middle-class Americans who went to a state school, like me, have known the definition of a complete sentence since age seven. (In case anyone is wondering, the answer is: subject, predicate - which essentially means verb - and complete thought.)

The combined result of Thatcher's decision that teaching English was supererogatory and the dim memories of people for whom parsing was punishment is written mayhem; my students use punctuation marks interchangeably, as ornamentation, and their malapropisms are worthy of a Restoration comedy (as are their proliferating capital letters). This spring I read about a character who wore "promiscuous clothes", and a novel that was "mellow-dramatic". One essay announced: "I will now offer a few examples to undermine my position". Another wrote of a character who has been misled by the promises of the American Dream: "This concept of her being an aspirant is shown through her excessive longing to be Ben Franklin." Their sentences aren't always this funny, but they're often this garbled, because students are guessing at grammar.

Don't misunderstand me: I firmly believe in people taking responsibility for their own education. We all have gaps that we must fill ourselves. But most of these students are working from a tremendous disadvantage - and mine are the so-called "advantaged" students.

Grammar has finally been reintroduced, in broad terms, into the national curriculum. But who's teaching it? Recent graduates. Textbooks are no longer given to schoolchildren; they're too expensive. So they're given to the teachers, who probably need them more. A former student of mine, who nearly failed her degree because her writing was so incoherent, asked me for a reference to study for her PGCE in English. I told her to study hard.

Top-up fees mean that universities are increasingly under pressure to confer degrees upon students, who perceive the degree as a commodity they've purchased. Failure doesn't enter into anyone's calculations.

This is also because of so-called affirmative teaching: students are taught how to give the correct answers to the questions they will be asked, and thus enter university with an entirely inaccurate sense of their own competence. These students seem to arrive at university expecting to have their existing knowledge and skills recognised, indeed "affirmed". It comes as a shock to them to discover that there may be limits to their abilities, or deficits in their knowledge - and they resent hearing it. Learning doesn't appear to be the goal. A colleague of mine recently received an aggrieved email from a student demanding that he stop using words in seminar that the student didn't understand.

The point is not pedantic. An impoverished understanding of their own language combined with an inflated sense of their own talents doesn't merely result in smug graduates with a beggared ability to express ideas. Sophisticated ideas cannot flourish in a linguistic vacuum. Expression and thought are inextricably linked: crude language permits only crude thinking. It's bad enough that these university students can't communicate their thoughts intelligibly; but those thoughts are themselves constrained by embryonic language skills.

And these are university students who are studying literature. The vast majority of the population, of course, believes that literature degrees lack "relevance" in the marketplace. Language can have surgical precision; the majority of my students can only employ it as a blunt instrument. What is the market value in that?

Let me put it in the nationalistic and commercial terms that seem to be the only discourse to which we attend any more: your students cannot compete with foreign students who have a better command of your native tongue than you do. In any arena that requires written communication, well-educated Americans and Europeans will wipe the floor with you.

There are, of course, a few happy exceptions. This year it was a group of four male friends, who worked ferociously hard for me and produced some sterling essays. One ended by describing a character's fate as "apraxia, in a bathtub". Look it up: I had to.

The writer is a senior lecturer in American literature and culture at the University of East Anglia