According to the degree of semantic independence of stems; according to the part of speech; according to the means of connection of stems; according to the types of stems.
According to the degree of semantic independence of stems compounds are:
1) subordinative - the components are neither structurally nor semanti-
cally equal in importance, the head member is the 2nd component:
baby-sitter, speedometer;
2) coordinative - both stems are semantically equally important, both
words are structural and semantic centres.
Coordinative compounds may be:
a) reduplicative - made up by repetition of the same word: fifty-fifty,
hush-hush, goody-goody;
b) phonetically variated rhythmic twin forms: chit-chat, zig-zag, clap
trap, helter-skelter;
c) additive - are formed from stems of the independently functioning
words of the same part of speech. They denote a person or an object that is two
things at the same time.
Functional classification - compounds are viewed as different parts of speech, which is indicated by the second stem:
- nouns: birthday, week-end, mother-in-law;
- adjectives: peace-loving, long-legged;
- adverbs: somewhere, indoors, inside;
- pronouns: somebody, something;
- connectives: within, without;
- verbs:
a) verbal and adverbial stems: to bypass, to inlay, to offset,
b) verbs formed by means of conversion: to week-end, to gooseflesh, to
blacklist.
According to the means of connection:
-formed by placing one simple stem with a linking element after the other: spedometer, Afro-Asian (o), handicraft (i); statesman, sales-man (s);
-without any linking element: headache, man-made.
According to the type of stems joined together:
-compounds proper: formed by joining together stems of words available in the language, with or without the help of special linking element, e.g. street-lamp, age-long;
-derivational compounds: one of the stems is derived, e.g. bed-sitter, type-writer, long-legged.
Patterns of Compounds Compound nouns: N + N - pencil-case [N + (V + er)] - peace-fighter
[N + (V + tion/ment)] - office-management, price-reduction
In general compounds are formed from the stems of words available in the language according to productive patterns: dog-days, rosy-cheeked.
Compounds can also be the result of a gradual process of semantic isolation and structural fusion of free word-groups, e.g.: forget-me-not, bread-and-butter, hook-and-ladder, man-of-war, up-to-date.
Compounding is a very interesting and problematic phenomenon. Though many investigations have been done in this field still there are many problems to be solved: typological study of patterns of compounds, motivation, compounds formed by means of conversion, the stone wall-problem (is it a free word-group or a compound word ?).