Function words: the essential guide

In Sentence 1 the words that have been replaced with nonsense are content words.
We know that such words carry meanings so we are quite capable of guessing what they are from the clues we have been given.  In that sentence we have:

• an adjective: glumpy
• nouns: finkleblender, dwoodledam, quitchicants
• verbs: bongle, flummber
• an adverb: bederously

None of these are real words, of course, but we know that they mean something.
In that sentence, too, we have retained the real English functions words and we know what these words do and how they link the others together.  In the sentence we have:

• the: the definite article.  We know that this is one way to define a noun.
• in: a preposition (usually).  We know that it serves to link a verb to a noun and give some information about where or when something happened so we get, e.g.:
      She waited in the station
      He arrived in the morning
  etc.
• and: a conjunction.  We know this operates to join ideas together to make longer sentences of phrases so we get, e.g.:
      She came and spoke to me
      I ate the apples and the yoghurt
      The house was cold and empty
  etc.
• all: a determiner which tells us what quantity of something we are referring to.  We can get, therefore, for example:
      all night
      all the time
      all of the children
  etc.
• my: another type of determiner which tells us who the noun belongs to, comes from or describes so we get, for example:
      my letter to the boss
      my house
      my reaction
      my problem
  etc.

In Sentence 2 all the function words have been replaced.
We have retained the content words (machine infuriated, extent, threw and immediately) but we have not shown how they are connected.  That makes it almost impossible to understand.

The moral of the story

The moral in the story is that meaning is made up not only of the meanings of the words but of the grammatical function and relationships between the words.  We need both to make any kind of sense.
Incidentally, the words that were replaced in sentence 2. were:

• that: a type of determiner called a demonstrative
• me: a pronoun referring to the object and standing for the speaker or writer
• to: a preposition with many functions
• such: a determiner in this case
• an: the indefinite article which appears before vowel sounds and refers to what we mean but not exactly which we mean
• that: the same word again but acting here as a conjunction to link ideas
• I: a pronoun but referring to the subject (the speaker or writer)
• out: a preposition which gives the opposite idea of in

If we put the function words into the sentence in that order, replacing all the nonsense words we get:
    That machine infuriated me to such an extent that I threw it out immediately.
All the nonsense words were in place of function, not content, words.

You should have this list:

There are some things to note:

1. Some verbs are considered function words.
   These include modal auxiliary verbs such as can, might, should etc. which only carry meaning combined with a content-word verb such as decide.  Standing alone, could has no obvious meaning but combined with imagine, for example, it does.
2. Some other verbs are similar.
   These include be, get, do and have.  These are only function words when they act to form part of a tense or other structure.  They are, in fact, primary auxiliary verbs.  For example, in:
       I have a house in Miami – the verb have is not operating as a function word here because it has meaning – i.e., own.
       I have been gardening – here, both have and been are function words because they are making a tense structure, not carrying meaning apart from a grammatical one.
       Do you want a drink? – here do is a function word which English uses to make a question form in some tenses.
       I'll do the work – here do is not a function word because it carries lexical meaning – i.e., perform.
3. There are some other words (sometimes called particles) which show the attitude of the speaker rather than carrying meaning per se.  Words such as Well, ..., if, but etc. do not always act as conjunctions joining clauses but can simply signal attitude.
4. Interjections such as ouch! certainly do carry meaning but, although they are usually considered content words, you can't actually define the meaning and it may shift depending on circumstances.  That word could mean, for example:
       She's singing off key
   or
       I have hurt myself.
5. Words like no, right, yes, maybe are also considered function words for similar reasons.  These are sometimes called pro-sentences because they can act as whole utterances in themselves.

The commonest words

In 1953, Michael West published what is known as the General Service Word List (the GSL) of the most useful words in English.  Of course, the list has been updated since then but the list of function words remains serviceable simply because these are closed-class items.  The original General Service List did not contain some nouns and verbs (such as computer and click) which are now frequent over 60 years later because times change.  Function words don't.
The list did not use frequency as the only criterion but it was the major one.

Only 26 of the top 100 words in both lists are content words and we are up to number 28 or 29 before we encounter the first of them (highlighted).  In the first 50 most common words, only 2 are content words.
The word computer by the way, comes in at number 421 and the word click does not appear in the first 2000.

The list of function words

Here is another list of the most common function words in English, divided into the four main categories.  The verbs which sometimes act as function words (see above) are not included.

In this list, articles count as determiners and so do demonstratives.
No attempt has been made to list interjections or pro-sentences.

Alert people will have noticed that some words appear in more than one column.  That's because they can function as different word classes in different environments.
Examples:

• another can be a determiner:
      I want another beer
  or a pronoun
  A beer was provided and another for my friend
  The word both can do the same sort of thing:
      I wanted both beers and both were provided
• either can function as a conjunction
      Either you do it or I must do it
  or as a determiner:
      Either beer will do
  or as a pronoun
      Please don't give me either
• since can be a conjunction
      I'll tell you since you ask
  and a preposition
      I have been here since Tuesday
• these can be a determiner:
      these beers are good
  or a pronoun:
      ... but these are better

and so on.

There's no proper test on this but to check you understand, identify the function words and what sort of functions they are performing in this sentence.
When you have done that, click here.

Can you tell me the difference between content words and function words?

A summary:

Here's a cut-out-and-keep aide memoire for function words:

Classroom implications

This section does not consider teaching approaches to function words.  There aren't any.  The range of types and functions means that lessons, or a series of lessons, can only sensibly be focused on small subgroups of function words such as:

• conjunctions which add information (additives) or those which contrast
• indefinite pronouns (any, some, every etc.)
• the definite article
• prepositions related to proximity (near, at, against, beside etc.)

1. Don't be tempted to think that because function words are so familiar to you that they will be easy for learners to understand and use.  All languages have ways of making relationships between content words clear and to do that they deploy all kinds of different functions but not necessarily function words as such.  Some languages will do it by adding suffixes to the ends of words, some by using different sorts of markers in sentences and so on.
   Even in languages which are similar to English (i.e., most European ones) the variations are enormous and complicated.
   This means that you will need explicitly to focus on what function words are doing in sentences and how they work.
2. Translation is fraught with problems.  It is relatively simple to translate many content words from one language to another (although where word meanings stop and start is an issue as are collocation, countability and connotation etc.).  So, for example, book is variously, Buch, boek, كتاب, libro, leabhar, βιβλίο, könyv, livre etc.
   This does not work with any but the simplest function words.
   Even something as simple as the idea of either ... or provides problems with many languages rendering it as something like or ... or (ose ose, vagy vagy, jew jew, ou ou etc.).  Other languages have a single word to stand for the concept and some use three words.  Don't assume for a second that any of the words for either in other languages can change into a determiner or a pronoun as the word can in English.
3. Don't rely on explanation.  Because of the variations in how people's first languages function grammatically (and function words are grammatical) learners need to see the words in action, understand the concepts they represent and deploy them to make their own meanings.  That means presenting, teaching and practising.
4. Keep the focus.  The lists above contain four different sorts of function words.  It makes sense to focus on a few of one sort only at a time.
5. Even within the groups, there are conceptual subgroups.  For example, within the determiners lie the articles and the English article system is itself complex and difficult to understand.  The same goes for the other groups.  Prepositions, in particular, are virtually non-translatable across languages and a source of persistent error and confusion.
6. Take opportunities to focus on function words which come up when you are doing something else.  They are so important that you should miss no chance to help your learners understand them and use them successfully.

For reference, the General service Word List is available from http://jbauman.com/aboutgsl.html and a good deal more information is available at http://www.newgeneralservicelist.org.

Try a short test to see if you can identify what sort of function words are in some sentences.