The Best Ways to Use Idioms and Expressions Naturally in Sessions Without Overwhelming Your Student
- Oleg
- 6 days ago
- 6 min read
At ENGin, volunteers hold thousands of English conversation sessions with Ukrainian students every week. Idioms come up constantly and how you handle them makes a real difference. In collaboration with betterclass, here's a practical guide to teaching idioms in a way that actually sticks.
Open any beginner idiom list and "it's raining cats and dogs" is sitting near the top, right next to "break a leg" and "the ball is in your court." Nobody has said "raining cats and dogs" in an actual conversation since roughly 1963, and yet it keeps turning up in ESL materials like a relative who won't take the hint and go home. Meanwhile, your student walks into a real conversation, hears "my bad," "that's on me," "no biggie," and has no idea what just happened.
Idioms are one of the fastest ways to make a student sound fluent. They're also one of the fastest ways to lose one completely, which usually happens for one of two reasons: you taught the museum pieces instead of the ones people say, or you taught eight of them in fifty minutes.
Three times or don't bother
Introduce an idiom once and move on and it's gone by next week. So stop fighting that and use a rule instead: don't put an idiom in a session unless you can get it out of your mouth three times naturally in that same session.
Say a B1 student is having a rough week. Your three slots might look like this:
Warm-up chat, unprompted: "ugh, sounds like a lot. hang in there."
Mid-session recap: "remember, if things get rough this week, just hang in there."
Signing off: "okay, hang in there, see you Thursday."
That's the whole thing. No flashcards, no drilling, no worksheet where they match the phrase to the picture of a cat on a branch. Three times in real context, and by the third one most students hand it back to you unprompted. If you can't find three natural slots for a phrase, that phrase isn't right for that session. Save in your notes for later.
They won't tell you they're lost
This is the part most teachers get wrong for years. Overwhelm almost never arrives as "sorry, I don't understand." Adults, especially, will not say that to you, partly because they're paying you and partly because nobody enjoys announcing it out loud. They'll quietly stop keeping up while you keep stacking phrases on top.
Things to watch for:
The blank stare that lasts half a second too long. Cheapest signal you'll ever get.
The student repeats your question back to you instead of answering it. Their processing is still two sentences behind.
Code switching, when someone who's been holding a full English conversation suddenly drops into their first language mid-sentence.
The polite nod with no follow-up question attached. This one fools everybody.
Engaged students ask things. Overloaded students agree with everything because agreeing is the fastest known route to the end of the lesson. If a student who normally interrupts you starts nodding along like a dashboard bobblehead, something has gone wrong.
Spot two of these in a row and stop introducing anything new for the rest of the hour. Just recycle what's already on the table.
This pattern shows up a lot in ENGin volunteer sessions too, especially with newer students who don't yet feel comfortable saying they're confused. The same signals apply, and the same fix works.
One theme, not a grab bag
A lot of idiom teaching fails the way a bad buffet fails. Five idioms about money, weather, feelings and sports crammed into one session is a lot to hold, mostly because none of it connects to anything else. Sushi next to the lasagna next to the chocolate fountain.
Pick a lane and stay in it. A money session gets:
break the bank
tighten your belt
cost an arm and a leg
Same mental folder. Your student builds one folder instead of five, and the phrases prop each other up because they show up in the same kinds of conversations.
Selfishly, it makes your review a hundred times easier. Next week you open with "so, still trying not to break the bank this month?" and you've reactivated the lot in one sentence, instead of squinting at your notes trying to remember what random assortment you threw at them.
"How do you say this in my language?"
Vocabulary survives translation reasonably well. Idioms mostly don't.
You're teaching "under the weather" and someone asks for it in Portuguese, or Ukrainian, or Turkish. The honest answer is usually that you don't, because most languages have nothing that means the same thing, in the same tone, in the same situations. Let them force it anyway and they walk out with a phrase that technically translates to "sick" and that they'll deploy in completely the wrong register the first time they try it on a coworker. You get the same effect if you translate French idioms into English, which is how you end up telling your boss you have the cockroach.
Stay in English instead. Build it from a scenario: you wake up, you're not sick enough to stay home, you just feel a bit off all day. Let the situation carry the meaning. It takes forty seconds longer and it actually sticks.
Say it before you teach it
The best idiom lessons don't open with "today we're doing idioms." They open with you using one before your student realises anything is being taught.
During the warm-up, before you've shown a single slide, mention you're swamped this week, or that a meeting ran over, or that you're running on fumes after the weekend. Say it the way you'd say it to a colleague, not the way it's written in a textbook dialogue. Let it land in the wild first. Circle back five minutes later with "hey, did you catch what I said earlier? swamped just means really busy."
It proves the phrase is something a real person says rather than something invented for ESL materials, and it quietly banks one of your three exposures before the lesson has officially started.
This works especially well in the kind of casual, low-pressure conversations that ENGin volunteers have with their students. No slides required, just talk.
Real content beats generic worksheets
For B2 and up, drop the manufactured idiom lists entirely. A handout called "15 idioms about weather" feels fake because it is fake, and students can smell it from the other side of the screen. A news clip or an article has idioms sitting inside real sentences, said by real people, in a situation your student can picture.
That's the whole idea behind betterclass's free lesson plans, and it's why teachers keep coming back to them:
Every session is built around a real article or video, so the vocabulary isn't picked to fill a grid. It's there because people actually say it.
The lessons come themed and leveled, which quietly solves the grab bag problem before you've even opened one.
Idioms turn up inside the reading and the discussion questions rather than in a box labelled "idioms," which is the difference between hearing a phrase and being handed one.
The feedback from teachers is consistently the same: students mention afterwards that they picked up a new word or phrase, without feeling like a vocabulary list got pushed on them.
That last point is the bar, honestly. If they noticed they learned something and you never announced you were teaching it, the session worked. Create an account on the site and run one with your next student.
Teach them to hunt on their own
Nobody teaches this part and it might be the most useful thing in the whole hour, because you won't be sitting there the next time your student hits a phrase that makes no sense.
Give them a few things to listen for:
Anything that doesn't make literal sense given the topic. Someone's talking about a deadline and says it's "not rocket science." No rockets present. Worth noticing.
A small shift in delivery. Idioms usually come with a bit of performance attached, a smile, an extra beat before the phrase lands.
Repetition from different people. The same odd phrase twice from two different mouths is not a coincidence, that's an idiom.
One more thing, and it somehow never gets said out loud: guessing is completely fine. Native speakers guess idioms from context constantly and get them slightly wrong all the time, which is why half the people using "beg the question" are using it wrong and nothing bad has happened to them.
None of this needs special materials. It needs some restraint from you and real content instead of invented lists. If you'd rather not rebuild that from scratch every week, betterclass already has plenty of it waiting, on topics your students will genuinely argue about.
If you're looking for more ideas between sessions, we've also put together guides on what to do when your session goes silent and how to use YouTube videos for conversation practice — both worth having open before your next call.
