AE 432 – Expression: Open a Can of Worms

Learn Australian English in this expression episode of Aussie English where I teach you to use the common English Expression OPEN A CAN OF WORMS like a native English speaker.

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AE 432 – Expression: Open a Can of Worms

This small valley in southern Australia is home to one of the rarest and the most extraordinary of all earthworms, and I know they’re around, because I can hear them. Those gurgling noises, believe it or not, are being made by giant earthworms as they squelch along their water-filled burrows. The vibrations of my footsteps are enough to stir them into activity. They never come to the surface, but in places where there’s been a small landslip, you can sometimes find burrows.  

G’day, you mob! How’s it going? Welcome to this episode of Aussie English. So, it has been a busy week, guys. I had my birthday. I have been working my butt off on vlogs and different videos on YouTube. I hope you’ve noticed and I hope you’ve been enjoying the new content on YouTube. So, I’m really trying to, I guess, show you everyday life and real English that native speakers actually use and how we interact with other people in these vlogs. So, that’s the whole purpose there. If you haven’t checked them out, make sure that you go over to YouTube, the Aussie English YouTube page, and have a look at the little vlog series that I’ve started putting together. Each of them tend to be about 10 minutes or less long. So, there’s a lot on there and I’m trying to do one a week, and I also just finished an accent video for you guys on the three different accents in Australian English. Now, I had done this previously, but I had made a few mistakes. So, this video was there to set the record straight and I reference Wikipedia. So, go and check that out.

Anyway guys, welcome to this podcast. This is the Aussie English Podcast and my name is Pete. I am your host and my job here is to help you guys learn Australian English, whether you want to understand Australian English, whether you want to speak like an Australian, or whether you just want to be able to understand what people are saying in all these different accents with all the different slang that we use, this is the podcast for you. Okay. And it is made possible by your support whether via Patreon or via Paypal power one-off donations. If you guys want to support this podcast, if you guys want to give back and help me do what I do, if I’ve been helping you learn English, then I really appreciate any donation, any donation no matter how small, no matter how large it is, it all goes towards helping me do what I do, and that is help you learn English.

It’s also brought to you by the Aussie English Classroom. So, this is the online classroom where you guys get access to all of the bonus content for these expression episodes, for the interview episodes. So, if you like studying and you want to do exercises, quizzes, and get bonus content all the empty threes and videos and everything like that, definitely sign up and give that a go. It’s just one dollar for your first month.

Anyway, today’s expression, guys. Today’s expression is “open a can of worms”. This is a really good one and I chose this one, because it’s common in every English-speaking country. So, no matter whether you’re in the U.S. or you’re in England, Ireland, Scotland, New Zealand, South Africa, Australia, you are very likely to hear “to open a can of worms”.

Intro Scene:

And that intro scene at the start there is related to Australia’s largest worm the giant Gippsland worm, which we’ll get onto in the Aussie English fact.

Anyway, time for the joke. Time for the joke, guys. So, the joke today is also related to worms, and I wonder if you get the pun. Okay. So, listen out for a play on words. Okay, so here’s the joke.

Aussie Joke:

What do you call it when worms take over the world? What do you call it when worms take over the world? Global ‘worming’… Do you get it? Global ‘worming’. So, the joke here is a play on words, it’s a pun, with the phrase ‘global warming’, and instead of saying ‘global warming’, you know, like the globe, the world, getting warmer and warmer, because of fossil fuels, we’re saying ‘Global worming’, because the worms have taken over the world. They’ve taken over the globe. Okay. So, another good pun joke there for you guys. I hope you enjoy it.


So, today’s expression is “to open a can of worms”. I wonder if you’ve heard this one before. So, we’ll go through the definition of the words in this expression, then we’ll cover the definition of the expression itself as well as its origin. We’ll go through some examples. We’ll go through a little exercise for you guys where you can practice your pronunciation, and then we’ll go through the fact today about Australia’s biggest worms.

Alright, so there’re few bits of vocab in this expression and they can mean various things.


So, “to open” something, “to open”, the verb “to open”. This can mean a few things can mean to, you know, open a store for business, make business available in a store when you launch that store. A bird can open its wings, so expand its wings, to start flying. And you can open a door or a window in order to, say, look outside or let air in. But in this case, “to open something” means to remove the lid or the cover of something so as to allow access to the contents. So, for example, you might open a jar so that you can have the jam inside the jar or maybe Vegemite. You might open a bottle of soft drink by removing the lid so that you can drink the soft drink. That is “to open”.

“A can”. “A can”. Okay, so “can” can mean to be able to. So, it can be a modal verb, but in this case, it’s a noun. Okay? “A can”, and “a can” is a cylindrical metal container. So, you could have a can of soft drink. You could have a can of tomato soup. That’s “a can”. It has to be metal.

“A worm”. Alright, so in this case, “a worm” is any number of creeping or burrowing invertebrate animals with a long, slender, soft bodies and no limbs. I’m sure you guys have seen a worm before, especially after it’s rained or if you were digging in the garden, you know, maybe you’re playing around with compost and the worms will be in the soil or they’ll be in your compost eating all your old veggies. So, that is what “a worm” is. They tend to be slimy, long, thin, little creatures.

Expression Definition & Origin:

Alright, so let’s go through the definition and origin of this expression. So, “to open a can of worms”, metaphorically speaking “to open a can of worms” is to examine or attempt to solve a problem, but then end up inadvertently complicating that problem or that situation and making it a lot worse. Okay. Literally speaking, though, “opening a can of worms”, as most fishermen can attest, can also mean more trouble than you bargained for. Right? Because if you open a can of live worms, the worms are alive, and they’re being used for bait when you go fishing, you might take one out and put it on your hook, and try and catch some fish, which is good, but the rest of the worms, now with the lid open, might go walkabout. So, they might start trying to escape. They might try fleeing. They might try crawling away. So, once you’ve open a can of worms, you’ve actually opened a can of worms, metaphorically, and now have a bigger problem on your hands.

So, the exact origin isn’t known. It’s not really clear where it was first used, but various dictionaries and historians believe that this phrase was from the US in the 1950s or maybe earlier, and it specifically references Oligochaetes. Okay? And they are the worms that you find in the soil. So, for the science nerds listening Oligochaetes or Oligochaetes, depending on how you pronounce the Latin word there, is the subclass of organisms that includes earthworms, worms that are found in the ground, and back in the day, before plastic and Styrofoam containers were ubiquitous, they were used everywhere, bait shops, shops that sold bait for fishermen, often sold earthworms and other live bait to fishermen, and these would come in metal cans with handles and lids.

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Alright, so some examples of how I would use the expression “to open a can of worms”. I’ll give you three of these guys. We’ll go through them step by step, and this should help you understand how to use this expression in context.


So, example one. Imagine that you’ve gone to a family dinner, maybe it’s a Christmas dinner, or maybe it’s someone’s birthday, but you’ve got your family around, and you guys are all chatting, you’re enjoying yourselves. Your father is an avid footy fan. He loves the team Essendon, the Bombers, Essendon. Whereas, your uncle is an equally avid footy fan, but he loves Carlton, The Blues, Carlton Footy Club. And these two teams have a long running rivalry. So, imagine that there’s a game coming up in a week or so and these two teams are going to play against each other, and you ask your father, “Who do you reckon’s going to win? Who do you reckon’s going to win between Essendon and Carlton?”. Obviously, your father’s going to say Essendon and your is going to say Carlton, and so by asking this question it might lead to a massive discussion, a big argument, a heated debate. And so, inadvertently by asking that question you’ve opened a can of worms. When you asked, “Which team do you reckon’s going to win, Carlton or Essendon?”. You opened a can of worms.


Example number two. Alright so, imagine you are a cop or a copper. So, a policeman or a policewoman, an investigator, someone who asks to solve a crime. Maybe there’s been a murder committed in your town and you have to sort out what happened. You’ve got to solve it. So, at first it seems like it’s a simple case. The suspect has been caught red handed and it seems like it’ll be an open and shut case, meaning that you open the case, you solve the case, because there’s so much evidence, and then you shut the case and move on. Open and shut case. You find out though that it is a great deal more complicated. Maybe the person who committed the murder was forced to commit the murder by someone else, maybe the Mafia or an organised crime group, and they’d forced him to do this because they’d kidnapped his wife, who had been kidnapped because she owed them money for gambling debts. So, you see how it’s getting a lot more complicated now. So, because it’s so much more complicated than you originally thought it was going to be, you could say, “When I decided to look into this crime that looked easy, it looked like it was an open and shut case, I inadvertently opened a can of worms. This crime led to a whole bunch of other crimes that had also happened and been related to this one that I also had to solve as a result. So, solving this crime led to a huge can of worms being opened.”. That’s example number two.


So, example number three. Imagine that you’re finishing high school and you have to make a decision now about which university you want to go to and what you want to study at that university. Maybe your parents have a certain idea in their mind, you know, they might expect you to do medicine or to do law or engineering, something they see as respectable that will earn you a lot of money and set you up to have a great life, but maybe that’s not where your passion lies. Maybe it’s not where your heart is. And maybe instead, your heart is set on becoming a primary school teacher or maybe becoming a social worker. So, when you finally summon up the courage to tell your parents your plans about studying social work or primary school education at university, it opens a can of worms. So, by telling them it inadvertently turns out to cause a huge number of other problems, arguments, fights, disagreements, maybe even your parents say, “Well, we’re not going to support you at uni financially unless you do a course that we want you to do.”. So, you’ve opened a can of worms. Telling them this thing has led to a whole bunch of other problems. Okay? Open a can of worms.

So, hopefully you understand the expression now, guys, “to open a can of worms”. It means to examine or attempt to solve a problem but end up inadvertently complicating it and making the problem or related issues even worse.

And I wonder, too, if you guys see the connection between this expression “to open a can of worms” and the expression “to let sleeping dogs lie”. Do you remember that one? That one was from episode 4-0-9, 409, to let sleeping dogs lie. So, these are kind of opposites. They kind of mean the opposite thing. So, for example if you do something that leads to more problems, you’ve opened a can of worms. Whereas, if you avoid doing something so as to avoid problems that it would cause, say, bringing up a topic in front of your family, you’ve let sleeping dogs lie. So, these are two really good expressions to learn that kind of mean the opposite of one another.

Anyway, guys, let’s go through the listen and repeat exercise, and then we’ll get into the Aussie English fact, and then I’ll let you get on with your day. So, the listen and repeat exercise, guys, is for you to practice your pronunciation. Repeat after me as best you can with your best Aussie accent or any English accent that you are currently working on, guys. And try and keep in mind, what is the intonation that he’s using? Is his voice going up? Is it going down? Is it speeding up? Is it slowing down? Is there connected speech happening? All of those things are going to help you become a better English speaker, but it starts by you trying to pay attention to them. Okay? So, listen to my voice and try and sound exactly the same. Let’s go.

Listen & repeat:


To open

To open a

To open a can

To open a can of

To open a can of worms x 5

I’ve opened a can of worms

You’ve opened a can of worms

He’s opened a can of worms

She’s opened a can of worms

We’ve opened a can of worms

They’ve opened a can of worms

It’s opened a can of worms

Great job, guys. Really good job there! Make sure that if you want the bonus content for this pronunciation exercise, which is usually a video, I normally go through step by step all of the components of connected speech and intonation and everything like that in a video, make sure that you sign up to the Aussie English Classroom, guys. And remember, it’s just one dollar for the first 30 days. So, you have an entire month to give it a go, to see if it’s what you like, to see if it helps you improve your English, before it will cost you anything else.

Aussie Fact:

Anyway, guys, let’s get into the Aussie English fact for today, and then we’ll finish up. So, the Aussie fact for today, I wanted to talk to you about Australia’s biggest worms. So, these are some famous worms from Gippsland and they’re called that giant Gippsland earthworms.

So, what’s Gippsland? Where’s Gippsland? Gippsland is a large portion of the state of Victoria and it comprises the east corner of the state. The state of Victoria is in the south east of Australia down the bottom of the country just above Tasmania, and it looks kind of like a triangle sitting on its side. So, it’s like a weird shaped piece of pizza, and Gippsland, the area, the region, is the tip of that piece of pizza. Okay? And there are many beautiful lakes and forests and beaches out there. I did my masters out there, actually, studying goannas. So, there are a lot of goannas out there. Lace monitors. These guys are really beautiful. (I) recommend that you look them up in Google. Lace monitors. Anyway, so, that is what and where Gippsland is.

What’s an earthworm? So, an earthworm is a burrowing annelid worm that lives in the soil and it’s important for aerating and draining the soil and in burying organic matter. So, this is why they’re so important for composts when we put our veggies and all our leftover food in the compost, we know it’s healthy when there are loads and loads of worms in there eating everything. So, you usually come across these guys when you’re digging in the backyard, mixing up the compost, or playing around with garden mulch, you know, or they might be on the footpath after a lot of rain. You might see them moving around if there’s been loads of rain.

Anyway, what is the deal with the giant earthworm from Gippsland? So, I’m just going to read through the Wikipedia page for today, because it was pretty short, and I’m going to chuck some quick clips in there too from the David Attenborough clip at the start of the episode, and you can see that via the link in this transcript if you want to watch the whole thing. So, here we go.

The giant Gippsland earthworm MegascoMegas… Let’s see if I can say this Megascolides australis is one of Australia’s 1,000 native earthworm species. So, let’s describe this species. What does it look like? How big is it? What’s its size? So, these giant earthworms average about a metre, so three and a half feet in length, and about only two centimeters, about an inch or so, in diameter or in width. However, the body is able to expand and contract making them appear much larger. On average they weigh about 200 grams, and they have a dark purple head and a blue grey body, and about 300 to 400 body segments.

So, if they can expand, though, you guys might be asking, “How do you know how fit they are or how long they are?”. Well, that’s a really good question. I’ll let David Attenborough answer this one.

So, the question is, “How long is a giant earthworm?”. Well, it’s not an easy question to answer. The fact of the matter is they’re rather delicate creatures and a break. If I was so unfeeling as to try and stretch it, well, I guess it might stretch to a couple of metres, almost six feet long.

Alright, so ecology wise, how do these guys live? How do they live? How do they interact in the environment? Where do you find them in the environment? So, these guys live in the subsoil of blue, gray, or red clay soils along stream banks and some south or west facing hills of their remaining habitat, which is in Gippsland in Victoria. So, they are living along streams like this because obviously the ground is wet and they’re living on south or west facing hills, because they’re the hills that aren’t receiving much sunlight. Right? So, they’re not heating up the soil. So, these worms live in deep burrow systems and they require water in their environment to respire, so in order to breathe they need water, they need to be kept moist.

They have relatively long lifespans, for invertebrates at least, and they can take up to five years to reach maturity. So, how long do these guys live until? David, can I handball you the question, mate?

How long they live, well, some say up to 20 years, but we really don’t know, and we certainly don’t know how they managed to mate deep underground as they squelch their way through their lonely tunnels.

So, they breed in warmer months and they produce egg capsules that are about four centimeters to seven centimetres in length, which are laid in their burrows, and these worms take about 12 months to mature, and when they hatch, they’re about 20 centimetres in length.

They’re usually very sluggish, but they can move rapidly through their underground burrows, and it can cause an audible gurgling or sucking sound, which allows them to be detected, like you heard at the start of this episode.

So, the Gippsland earthworm colonies are small and isolated and the species’ low reproductive rates and slow maturation make those small populations very vulnerable. Their natural habitats are grasslands, and while they can survive beneath pastures, cultivation, heavy cattle grazing, and effluent runoff are adversarial to the species.

So, there used to be a museum, guys, out in Gippsland that used to be able to go and see if you wanted to see these worms, and I think I went there as a kid, but I just learnt, whilst reading this Wikipedia page, that it closed in 2012 amid animal welfare concerns.

So, the Wildlife Wonderland Park near Bass in Victoria was home to the Giant Earthworm Museum, and inside the worm-shaped museum visitors were able to crawl through a magnified replica of a worm burrow and a simulated worm stomach and displays and educational material on the giant Gippsland earthworm and other natural history of the Gippsland were also featured there, but unfortunately, (it) sounds like you can’t go and see it anymore.

So, anyway guys, that’s it for today. I definitely recommend going and checking out the BBC’s Life in the Undergrowth documentary series with David Attenborough. The link to the video will be in the transcript, if you would like to see the video from today’s episode.

Anyway, I hope you have an amazing week, guys. Thanks again for listening. Oh! And, a quick mention, if you guys want to support the podcast, please don’t forget to give it a share, give it a like, comment on the videos, and also give it a review if you can on any platform that you listen to this on. Right? So, on iTunes, Stitcher, whatever it is, every review helps. So, that’s what I would really appreciate if you want to help the podcast grow.

Anyway, I’ll chat you soon, guys. All the best!

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