As I mentioned in my last blog, there are heaps of native English speakers (even very well-educated ones) who don't always use English well. I've already picked on football pundits: paid handsomely to talk for a living, they still struggle to speak the lingo to the standard you'd expect. But what about the average Joe on the street?

Well, the thing is, most people know roughly how well they speak their own language, regardless of where they went to school or what job they do. But plenty aren't all that worried about making the same errors every time they open their mouths.

And as we all pick up language mainly by listening to others, it's no surprise that poor English spreads faster than a wildfire in the Australian outback.

As an English teacher, what concerns me is how often learners pick up bad habits from native speakers on the telly or in the local pub. But I'm not suggesting for one minute that everyone whose first language is English should sound like a BBC newsreader. All I'm saying is that learners need to be aware that many native speakers are just as likely to use poor grammar as learners are.

That's why English-language students should listen to a broad mix of content when practising – not just the audio from their language school courses and the like. And remember that not everything you hear in the language you're learning is worth copying if your goal is to speak it well!

English learners, let me know what you think of this article – and remember, don't believe everything you hear out there :)

Just for fun, here's a short article with five common mistakes made by native English speakers when speaking or writing. Can you spot them all? The answers are at the end of my next blog.

Me and my mate went to the pub on Saturday to watch the match. It was quieter than usual, with less people than last week, so we grabbed a table right in front of the big screen. 'We should of arrived earlier,' said Dave. 'The atmosphere's better when it's packed.' Then the home side scored. 'I seen that striker play for his old club once,' I said. 'He's brilliant.' At half-time, Dave asked if I'd remembered to book tickets for next week's game. 'Of course,' I said. 'I done it online this morning.'

• Heaps of – a lot of

• Speaking the lingo – speaking the language of a particular place or group

• The average Joe – a regular, ordinary person

• Telly – British informal word for television

• Pick up – to learn something informally, often by copying