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Concourse 2

Idioms: the essentials

bite the bullet cat out of the bag
bite the bullet let the cat out of the bag

What are idioms?

Idioms are expressions whose meaning is not apparent from the meanings of the individual words.  For example, the two idioms above mean respectively to suffer something unpleasant but unavoidable and to betray a secret.
They mean these things because speakers of English agree that they do.  The origins of many idioms are often obscure and debated.
All languages contain very large numbers of idioms (one estimate for English puts the figure at 25,000) and they are troublesome for learners for three reasons:

  1. You can't figure out what they mean even if you understand all the words individually.
    You may understand
        He's pulling your leg
    to mean that someone is playing a joke on you by telling a lie but you can't extract that meaning by understanding the verb and the noun.
  2. You can't usually change the order of the words, leave any out or insert other words so you have to learn the whole chunk as a single item.
    You can't say
        Release the cat from the bag
        Let the lion out of the bag
    and expect the meaning to remain.  You also can't usually say something like
        Let the cat out
        Let the tortoiseshell cat out of the bag
    and retain the meaning of the idiom.
    You can, however, often change some of the grammatical or function words, such as pronouns or determiners and occasionally we can make nouns plural so we can make:
        She's pulling your leg
        They are pulling everyone's legs
  3. Idioms rarely if ever translate word-by-word from language to language.  You may think that let the cat out of the bag is easy enough to understand but if you translate it into another language it is usually meaningless or will be taken literally.  The idea will translate but not the words themselves.



The first of these problems is sometimes referred to as opacity.  Some idioms are more opaque than others, however.  Which of the following are the easiest to understand for a non-native speaker of English?
Click here when you have an answer.

  1. a can of worms
  2. a drop in the ocean
  3. a piece of cake
  4. a back-seat driver
  5. find your feet
  6. in the heat of the moment
  7. kick the bucket
  8. smell something fishy

The second problem above is the extent of fixedness, i.e., how much the idiom may be changed without losing the meaning.  Which of the following are completely fixed and which allow some room for innovation?
Click here when you have an answer.

  1. throw in the towel
  2. smell a rat
  3. under the weather
  4. on tenterhooks
  5. hale and hearty
  6. out and about
  7. use your loaf

As we noted above, idioms (and binomials in particular) very rarely translate exactly but it is interesting (to some) that the notions and ideas they contain do translate, albeit with different words.  Here are some examples for fun.  Can you match the English idioms on the left to their equivalents in other languages on the right?  Click on the image when you have an answer.

idiom translation


Teaching idioms

There's nothing mysterious about teaching idioms.  Treat them as single items of vocabulary (lexical chunks) and teach them the same way you teach any other vocabulary items.  See the guide to teaching vocabulary, linked below, for some ideas and more.
But bear style in mind and do not try to present idioms in inappropriate contexts or texts.  Idiomatic expressions are very frequently used in newspaper headlines and that is a good source of exemplification.

In the section for learners on this site, there are some exercises to do with idioms and binomials.  Check under vocabulary for more.

There is a more complete and more technical guide in the in-service section of the site which repeats much of the above adding detail and lots of classifying terminology.

Related guides
teaching vocabulary for some ideas about the general area and how to teach words
guide to idiomaticity a more detailed and difficult guide in the in-service section
the exercise index for some exercises in this area for learners