There are "extensive linguistic differences" between different registers of English (Biber et al., 1999, p.9). Academic and conversational registers reveal a complementary frequency distribution of vocabulary and grammatical forms. Some of the principle differences are as follows:
- Conversation has a lower density of information and therefore fewer nouns (Biber et al, 1999, p. 66). 60% of lexical words in academic prose are nouns (p. 65). Plural nouns are used 3-4 times more in academic prose than conversation (p. 291). Nominalization is much more common in academic prose than other registers, especially –tion and -ity (p. 322).
- Adjectives are least common in conversation and most common in academic prose, The comparative form is used three times more often in academic prose than in conversation. Conversely, superlatives are more common in conversation than in academic prose (p. 65).
- Conversation is marked by a high frequency of pronouns and a low frequency of nouns (p. 1042). The Words like everybody, everyone, everything, somebody, anybody, anyone, anything, and nobody are common in conversation but rare in academic writing. Conversation uses pronouns in anaphoric expressions (to refer to an already established idea), whereas academic writing uses definite noun phrases in anaphoric expressions (p. 266). Preposition+which relativizers are only common in academic prose (p. 625).
- The determiner that is 11 times more common in conversation than in academic writing, where it is relatively rare. This, used as a determiner, is more common in academic writing than in conversation, occurring 2500 versus 1500 times. The big exception is with the phrase this one which occurs 3000 times in the conversation corpus and not at all in the academic written corpus.
- Conversation has shorter clauses, and so verbs and adverbs are much more frequent in conversation and fiction (because it contains quoted speech) and much less frequent in academic prose (p. 65). Certain verbs are particularly common in conversation and particularly rare in academic prose: try, buy, put, pay, bring, meet, play, run, eat, watch, pick, wear . Negation is most common in conversation and least common in academic prose (p. 159). Only in conversation is the progressive used to emphasize the reported message itself as in, “She was saying…” (p. 1120). Across all registers, 85% of verbs are tensed, while 15% of verbs are modal constructions (p. 456). Modals are most common in conversation and are about half as common in academic prose (p. 456). The progressive aspect is more common in conversation than in academic prose. The present perfect is about 30% more common in conversation than in academic prose (p. 461). Have/has got is the most common present perfect verb in any register, occurring over 1000 times per million words in conversation, but less than 20 times per million words in academic prose (p. 465)
- “But” is more frequent in conversation and fiction, and less frequent in academic prose. “And” is more frequent in academic and fiction than conversation and news. In conversation, “and” is used as a clause level connector. In academic prose, and is used as a phrase level connector (p. 81) .
- Verbs and "not" are contracted most frequently in conversation and fiction. Verbs are contracted less than 2.5% of the time in academic prose, and "not" is contracted 5% or less. (p. 1132)
- The word since is used to introduce a reason in academic prose 95% of the time, but it is used to indicated a point in in time in all other registers (p. 848). The word while is used for concession in 80% of occurrences in academic prose, but it is used for time references 100% of occurrences in conversation (p. 849). The word though is used primarily as a linking adverbial in conversation but as a subordinator in written registers (p. 850).
- Expressions like see if, wonder if, know if and ask if are common in conversation and rare in academic prose. Know whether is 8 times more common in conversation than in academic writing. Determine whether, the most common post predicate wh-clause in academic prose, occurs 20 times in academic writing and not at all in conversation (p. 692-693).
Biber, D., S. Johansson, G. Leech, S. Conrad and E. Finegan (1999), Longman grammar of spoken and written English. Harlow: Pearson Education.