Sarah Smith, 43, said she lived in fear of her pupils or their parents noticing her spelling and grammar mistakes

My hands were feeling clammy and beads of sweat broke out under my collar as I shifted nervously in my seat. It was parents’ evening.

As a teacher with six years’ experience, you might imagine that I would have been in my element as I chatted about the eight-year-olds in my charge and offered their parents encouragement and advice.

Instead I was consumed with embarrassment. And no wonder. The father opposite me — a lawyer — was looking at me as if I was dirt under his shoe.

I had been telling him about the new drive to improve literacy standards in our school when he had interrupted me.

‘Can you repeat what you just said?’ he said. ‘I’m not sure I could possibly have heard you correctly.’

I had no idea why he was getting so agitated. To humour him, I repeated slowly: ‘I said that me and the headmistress are doing all we can to improve standards.’

I might as well have told him that we were planning to bring back the birch. Throwing his hands up in the air, he launched into a tirade that left me red hot with shame.

‘Me and the headmistress?’ he ranted. ‘Don’t you know it should be: “The headmistress and I”? How can you call yourself a teacher when your grammar is so poor?’

I wanted the ground to swallow me up. Many years later, I still feel there was no excuse for his rudeness, but I can understand why he was so angry. I’d feel the same if a child of mine was being taught by a teacher like me.

And the shocking truth is that there are thousands of teachers in schools the length and breadth of the country who are just like me.

We have degrees in English from respectable universities, yet wouldn’t know a subjective pronoun from an objective one if it hit us in the face.

I joined the profession in 2005 and quit last year, eventually worn down and depressed at seeing a generation of schoolchildren let down by an education system that not only allows woefully ill-prepared teachers like me into the job, but doesn’t pick up on our failings.

For the truth is that I had no idea I had said anything untoward that day. And most of my colleagues — experienced, highly qualified teachers in their 30s and 40s — wouldn’t have known either.

The products of a liberal education system that eschewed the ‘rules’ of the English language for trendy educational methods, we were as bemused as the children we taught. So how on earth are teachers going to deliver the Government’s demanding new school curriculum with its emphasis on grammar?

Alice Phillips, the president of the Girls’ Schools Association, caused uproar last week by admitting that when it comes to grammar, even university-educated English teachers like me are at sea.

Mrs Phillips said that when she’d introduced a grammar course for 11-year-olds at her fee-paying school — St Catherine’s, Bramley, near Guildford, Surrey — she’d been shocked to discover that some of her staff were ill equipped to teach it.

‘Many of our brightest, most enthusiastic teachers have little or no grounding in English grammar,’ she said.

‘They are completely at sea with many aspects of proper usage.’

The problem is so bad that two years ago, the head of my inner city primary school in South Yorkshire had to employ a literacy expert — to teach the teachers.

Our grasp of grammar and spelling was so poor that we couldn’t even be trusted to teach children aged four to eight.

I always found it particularly stressful towards the end of term when I knew that I’d be put on the spot when writing school reports. It used to cause me endless sleepless nights — not because of my assessments of the pupils, but my poor spelling.

Ms Smith said she was not taught the basic rules of grammar at any point during her education and blames that on Harold Wilson's government axing the 11-plus

I used to write achieve as ‘acheive’. ‘I before e’ was never my strong suit. Thank heavens the head was there to correct such errors before the reports were sent off to the parents. She was the one we relied on to make sure our spelling mistakes were never discovered.

If only the parents had seen our internal memos and emails — ‘your’ instead of ‘you’re’, missing apostrophes from ‘its’, wrongly added apostrophes in words such as ‘pie’s’. The clangers were horrific.

And then there was the time I prepared a lesson on nutrition and vegetables. Thankfully, a colleague, not one of my pupils, changed ‘brocolli’ to broccoli.

I used to live in fear of the children pulling me up on my spelling. One morning I asked my class for their ideas on a subject, which I would then write on the board.

One boy called out the word ‘simultaneously’. I struggled to spell it twice and in the end had to give up and write ‘at the same time’.

My apparatus cupboard had even been labelled ‘aparratus’ until one of the smarter children in the class piped up: ‘Miss, are you sure that’s spelt right?’ Mrs Phillips blames the problem with teachers’ grammar on the shocking education standards of the past.

She’s right. And I’m afraid the knock-on effect will be felt for generations to come.

The stark truth is that most people educated in a state school in the Seventies and Eighties had little or no grounding in grammar. And many of us have become teachers. Scarred ourselves, we have passed the damage on.

I’m convinced the rot started in 1964 when Harold Wilson’s Labour government came to power and abolished the 11-plus in many areas. Parents were told this was to enable primary schools to develop a more informal, child-centred, progressive style of teaching, with the emphasis on learning by discovery.

We have degrees in English from respectable universities, yet wouldn't know a subjective pronoun from an objective one if it hit us in the face

As a teacher, I can see this is rubbish. The belief that grammar could be ignored was virtually all pervasive until 1988, when the Conservative government introduced the National Curriculum.

I’m 43 and from the day I started junior school in Solihull in 1979, I experienced a grammar-free education until I left comprehensive school in 1987.

For me and many of my peers, there is a vast chasm in our knowledge and basic abilities. While previous generations had grammar drilled into them and were taught by rote, we were encouraged to get ‘a feel’ for sentences.

This left me with a terrible grounding in the three Rs. Basic grammatical rules elude me. When do you use ‘which’ or ‘that’? Is the bag ‘hers’ or ‘her’s’? Until recently, I didn’t even know there were different types of nouns.

I wasn’t taught any of this at secondary school. I even managed to get a degree in English literature from Sussex University — the alma mater of novelist Ian McEwan — without anyone pulling me up on my diabolical use of the language.

And I sailed through my teacher training as a mature student before landing my first job in a state primary school in South Yorkshire.

I had been in the job only a few weeks when I learned, with a sickening sense of dread, that part of my literacy duties was to instruct my nine-year-old pupils on the use of ‘modal verbs’.

I had never heard of them and rushed home that night to research them on Google. Only then did I discover they are words such as ‘can’ and ‘could’, ‘shall’ and ‘should’, which are used to describe if something is certain, probable or possible .

As I furtively mugged up on them overnight, I felt ashamed. I was also terrified that I would be caught out.

After all I was only one small step ahead of my pupils, and with a horrible, haunting feeling of being a fraud.

Most of the parents — products of the same dire education system as me — were as much in the dark about grammar as me.

But I will never forget the embarrassment of being publicly humiliated at that parents’ evening. As other parents craned their necks to hear what was going on, I felt intense shame. And I knew I deserved it.

At least I realised my shortcomings and was conscientious enough to do my own homework to fill in the gaps. I always planned my lessons. If that meant I had to teach myself first, I did so. But some teachers feel there was no need to understand all those ‘tricky bits’.

There’s also the issue of teaching assistants, many of whom are excellent and work tirelessly for poor pay. But I’ve seen comments such as ‘thats grate’ or ‘your a star’ on children’s homework.

They would congratulate children who had done well by saying ‘it were easy for you’.

I would interject: ‘We say “I should have” rather than “should of.” ’

But there are only so many times you can correct people without looking like a bully.

In my experience, one in five children left primary school without the basics.

Luckily, some children have parents, such as that bad-tempered lawyer father, who can help them. But, sadly, many don’t and those are the ones who are truly failed by teachers.

Thankfully, I had the good grace to quit teaching and take a job in the media.

I now experience parents’ evenings on the other side of the desk, as a mother to a nine-year-old and five-year-old.

So far, I haven’t encountered any terrible grammatical clangers to match my humiliation, but yes, mistakes are still being made.