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Structure (function) words versus content (lexical) words

See also Youtube  structure words list

Since C.C. Fries's Structure of English (1953), language teachers have described English words as falling into two broad types: those that belong in the dictionary like 'storm' and 'confabulate', called content or lexical words, and those that belong in the grammar like 'of' and 'the', called structure, function or grammatical words. To see the difference, here is a quotation from a Theodore Sturgeon story using made-up content words but real function words:

So on Lirht, while the decisions on the fate of the miserable Hvov were being formulated, gwik still fardled, funted and fupped.

If the same sentence were rephrased with made-up function words and real content words, it would read:

So kel Mars, dom trelk decisions kel trelk fate mert trelk miserable slaves hiv polst formulated, deer still grazed, jumped kosp survived.

Here are some of the main differences between structure and content words:

Content Words

Structure Words

- are best explained and listed in the dictionary, like 'book', 'teddy bear' or 'encapsulate' - are best explained in the grammar, i.e. in terms of how they fit  into sentences: 'f'the' is a definite article that goes with nouns
- exist in large numbers, tens or hundreds of thousands, as seen in any dictionary - are very limited in number, consisting of 220 or so in English
- vary in frequency from common words like 'beer' to very rare like 'adduction' (6 times in a 100 million words) - are mostly very high frequency, for example all the top ten for English and 45% of the top 100 are structure words
- are used more in written language - are used more in spoken language
- are more likely to be preceded by a pause in speech 'I like … bananas', perhaps because there are more to choose from - are less likely to be preceded by a pause in speech 'I hate …the referee', perhaps because there are less of them to choose from
- consist of Nouns ('glass'), Verbs ('move'), Adjectives ('glossy') etc - consist of Prepositions ('to'), Articles 'the'), Auxiliaries ('can') etc
- are always pronounced and spelled in essentially the same way; 'tree' is always said with the same consonants and vowel  - vary in pronunciation for emphasis etc; 'have' can be said as /v/, as /hv/ with a change of vowel and as /v/ ('ve)
- usually have a fixed stress or stresses; 'theatre' is always 'theatre' /'it/) never 'theatre' /i't/ - are usually unstressed but given stress for emphasis etc; 'I've done it/I have done it/I have done it'
- usually have more than two letters, as in 'eye', two', 'inn' - can consist of one or two letters, as in 'I', 'to', 'in'

- starting in 'th' are pronounced with a voiceless 'th' // 'think', 'theme'

- starting in 'th' are pronounced with a voiced 'th' // 'this', 'them', 'there'

- can always be invented – I heard 'vagueity' on the radio this morning. Virtually all the new words coming into the language say 'cyberpunk', are content words.

- can never be invented, apart from changes over time. One attempt was 'per' for 'he/she', which has never caught on. See Pronouns and Power

List of English structure words

Grammar in language teaching (paper)

How children learn words

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