15 Common English Idioms

Has this ever happened to you? 

You’re talking with an English speaker and everything is going well. Until . . .

What did they just say? They go out dancing once in a blue moon? 

That doesn’t make any sense!

This confusing expression is called an idiom, and English is full of them. 

What Is an Idiom?

An idiom is a word or phrase that means something different than the literal meanings of the words. Idioms are popular expressions that are understood because they’re used so often. 

In the example above, once in a blue moon simply means rarely. In other words, your friend rarely goes dancing. 

Are you ready to learn more of these strange expressions? 

Read on!

15 English Idioms

1. A piece of cake 

→ Simple to do 

I got 100% on my math test. It was a piece of cake!

2. To break even

 → To neither gain nor lose money

I didn’t win any money at the casino, but I didn’t lose any, either—I broke even.

3. To break the ice

→ To do or say something to relieve tension or start a conversation when you’re first meeting someone

The students were nervous on the first day of class, so the teacher told a joke to break the ice.

4. To cost an arm and a leg

→ To be very expensive

I didn’t go to the concert because the tickets cost an arm and a leg.

5. Couch potato

→ A lazy person who sits on the couch watching a lot of television

I get so tired after working all week. On the weekends, I’m such a couch potato!

6. To cut corners

→ To save time or money by doing less work than you should

My new house has a lot of problems; I think the builders really cut corners!

7. To feel under the weather

→ To feel slightly sick

I’m going to stay home from work today; I’m feeling under the weather.

8. To hit the books

→ To focus on studying

I’m not ready for tomorrow’s English grammar test! I need to hit the books tonight!

9. To hit the sack

→ To go to bed

I am SO tired today. I’m looking forward to getting home so I can hit the sack.

10. Not (someone’s) cup of tea

→ Something that someone doesn’t like

Can you change the playlist? This music isn’t my cup of tea.

11. To pitch in

→ To help with an activity or task

This house is a mess! We’ll be able to clean it faster if everyone pitches in.

12. To see eye to eye

→ To agree 

I think I want to find a new job. My manager and I never see eye to eye.

13. To sit tight

→ To wait patiently

-Mom, when is dinner going to be ready?

-We’ll eat in about 25 minutes. Just sit tight!

14. To twist (someone’s) arm

→ to convince someone to do something

I didn’t want to go to the party, but I went because my best friend twisted my arm. 

15. Up in the air

→ Uncertain; unknown

I was going to travel to Europe with my friend, but she canceled. Now my plans are up in the air.


Idioms are everywhere! Try learning some of the most common ones and using a few in your next English conversation. Before long, it’ll be a piece of cake!

Andrea is a Gabby Academy coach and education technolgy writer based in Vancouver, Canada.