I am a pedant. There is no question about it. Everyone I know would agree, and I accept and embrace it. I have no problem with being called a nerd, or a geek, or any synonyms of these words. I watch the BBC programme QI, and I have read the quiz show's Book of General Ignorance, which has prompted frequent corrections of my friends' and family's mistakes.

In addition to this, I get frustrated about incorrect grammar. Earlier this year, I wrote to Tesco because its orange juice informed me that the oranges were squeezed at their "most tastiest". To my surprise, Tesco actually responded with a promise to change the packaging.

My history teacher is rather a grammar fiend, and I told him about the incident. One of my classmates, who shares my sense of irony, suggested jokingly that I write to the Sun newspaper as it would probably make the front page.

I decided to do so (to many papers, including the Sun), not simply to see if they would publish it but also because I was genuinely shocked by Tesco's command of English. Generally, I try to hold back the temptation to correct people. My friends and family get quickly irritated if I point out their mistakes, and I have tried to accept that people make errors in speech, as they often just blurt things out with little thought (especially as my friends are all 15- or 16-year-olds).

However, I really feel it doesn't send out a very good message when multinational companies such as Tesco, and more recently BMW (with its "bites as bad as it barks" slogan), make such glaring mistakes. Personally, I am willing to accept some errors – I wouldn't hassle someone over their use of "who" rather than "whom" – but I can't believe some of the errors companies make.

I decided that the best way to get my point across about large companies setting a good example was to write an exaggerated and slightly sarcastic letter. I hoped to amuse my friends, and the editors of the newspapers, but there was a point to be made.

I do understand that many people believe it to be a good thing that language develops. I agree with this in part, but feel that the basic rules of the English language should be adhered to. However, I still feel that we should keep to the simple rules of grammar that children learn every day in primary school, especially in advertisements, where everything is planned extensively.

There is an ongoing feud between those who care about grammar and those who don't, as shown by the comments about my antics with Tesco and BMW. I have been both insulted and called a hero by the online readers and tweeters.

I think I am somewhere between the two. In all honesty, I feel the English language should be respected and used correctly most of the time, but I am also willing to accept that some parts of it will change. Whatever would we do without twerking and selfies, eh?