爱思英语编者按：学外语是为了和外国人沟通，学语言当学地道的表达，学英语必须知道的20条英语俚语，你知道该怎么用吗？

20 Common English Idioms You Should Probably Know

Those of us who grew up with English as our first language have been exposed to idioms and idiomatic expressions for most of our lives. They may have confused us a little when we were children, but explanation and constant exposure not only increased our understanding of them, but likely drew them into our own vernacular. If you’re in the process of learning the English language, you may come across some of these and not be entirely sure what they mean. Here’s a list of 20 that you’re likely to come across fairly often:

1. A Chip on Your Shoulder
No, this doesn’t mean that you’ve dropped part of your snack. To have a chip on one’s shoulder implies that the person is carrying around some grudge or bad feelings about something that happened in the past… like having walked through the wreckage of a building, and ended up with a chip of that building stuck to them for years afterward.

2. Bite Off More Than You Can Chew
Like taking a HUGE bite of a sandwich that will fill your mouth up so much that you can’t move your jaw, this idiom implies that you’ve taken on more than you can handle successfully. An example would be agreeing to build ten websites in a week when normally you can only handle five.

3. You Can’t Take It With You
You can’t take anything with you when you die, so don’t bother hoarding your stuff or not using it except for “special occasions”. Live now, because all your stuff is going to be around long after you’re gone.

4. Everything But the Kitchen Sink
This implies that nearly everything has been packed/taken/removed. For instance, if someone said: “The thieves stole everything but the kitchen sink!” it meant that they took everything they could carry; it’s damned hard to remove a sink and carry it around.

5. “Over My Dead Body”
When the only way you’ll allow something to happen is if you’re no longer alive to stop it.

6. Tie the Knot
To get married. This is left over from the old tradition of handfasting, wherein the hands of the bride and groom would be tied together with a length of ribbon to symbolize that their lives were fastened together permanently.

7. Don’t Judge a Book By Its Cover
Things aren’t always what they appear to be at first glance, so it’s a good idea to give something a chance, even if its outward appearance isn’t immediately attractive.

*The exception to this might be actual books that have hideous covers: those tend to be terrible all around, and in cases such as these, it’s best to contact the author or publisher and recommend a good graphic designer.

8. When Pigs Fly
This means “never”. Pigs aren’t about to sprout wings and take flight anytime soon, so if someone says to their kid that they can get a forehead tattoo when pigs fly, it’s not gonna happen.

9. A Leopard Can’t Change His Spots
Basically: you are who you are. Just like a leopard can’t concentrate really hard and change the pattern on its skin, people can’t change who they really are at heart.

10. Wear Your Heart on Your Sleeve
To freely show and express all of your emotions, as though your heart were on the outside of your body.

11. Bite Your Tongue!
Stick your tongue between your teeth (gently), and then try to speak. You can’t say a word, can you? To bite one’s tongue means to stay quiet: literally to hold the tongue still so it can’t make a sound. This goes along with:

12. Put a Sock In It
The idea behind this is that if you stuffed a sock in your mouth, you’d be quiet… so if you tell someone to “put a sock in it”, you’re telling them to shut up.

13. Let Sleeping Dogs Lie
If a couple of dogs had been fighting and are now sleeping peacefully, it’s best to just leave them alone. The idea behind this one is to avoid bringing up old arguments so they’ll just be argued about again.

14. Foam at the Mouth
To hiss and snarl in anger like a rabid dog (whose mouth would be foamy as he jumps around like crazy and tries to bite people).

15. A Slap on the Wrist
A very, very mild punishment. To be slapped on the wrist doesn’t hurt much, and isn’t a deterrent from misbehaving again.

16. You Are What You Eat
This is the idea that everything you eat influences your health and well-being. If you eat nothing but junk food, you’ll end up unhealthy and malnourished, so be sure to eat a well-balanced diet.

17. “It’s a Piece of Cake!”
…meaning that it’s incredibly easy. No-one has a difficult time eating a piece of cake, do they?

18. It Takes Two to Tango
A person can’t dance the tango alone, nor can they fight by themselves either. If an argument has occurred, there were two people involved, so two were responsible.

19. Head Over Heels
To be incredibly excited and joyful, particularly with regard to being in love. Imagine someone so happy that they do cartwheels down the street: like that.

20. An Arm and a Leg
When something is so ridiculously expensive that you might have to sell your own body parts in order to afford it, it’s said to cost “an arm and a leg”.