Word-formation

Prefixation is the formation of words with the help of prefixes. Prefixes are derivational morphemes affixed before the derivational base. Prefixes modify the lexical meaning of the base. They seldom shift words from one part of speech into another and therefore both the source word and its prefixed derivative mostly belong to the same part of speech, e.g. to rewrite < to write.
Prefixes can be classified according to different principles.
1. According to the lexico-grammatical character of the base prefixes are usually added to, they may be:

1. 
   deverbal (those added to the verbal base), e.g. re- (rewrite); over-overdo); out- (outstay);
   
2. 
   denominal (those added to the nominal base), e.g. un- (un­button); de- (detrain); ex- (ex-president);
   
3. 
   deadjectival (those added to the adjectival base), e.g. un-(uneasy); bi- (biannual).
   

2. According to the class of words they preferably form prefixes are divided into:

1. 
   verb-forming prefixes, e.g. en-/em (embed, enclose); be-(befriend); de- (dethrone);
   
2. 
   noun-forming prefixes, e.g. поп- (non-smoker); sub- (sub­committee); ex- (ex-husband);
   
3. 
   adjective-forming prefixes, e.g. un- (unfair); il- (illiterate); ir-(irregular).
   

d) adverb-forming prefixes, e.g. un- (unfortunately); up- (uphill). It should be specially mentioned that the majority of prefixes function in more than one part of speech.
3. Semantically prefixes fall into:

1. 
   monosemantic, e.g. the prefix ex- has only one meaning 'former' — ex-boxer;
   
2. 
   polysemantic, e.g. the prefix dis- has four meanings: 1) 'not' (disadvantage); 2) 'reversal or absence of an action or state' (dis­economy, disaffirm); 3) 'removal of (to disbranch); 4) 'completeness or intensification of an unpleasant action' (disgruntled).
   

4. According to their generalizing denotational meaning prefixes fall into:

1. 
   negative prefixes, e.g. un- (ungrateful); поп- (nonpolitical); in-(incorrect); dis- (disloyal); a- (amoral);
   
2. 
   reversative prefixes, e.g. un₂- (untie); de- (decentralize); dis₂-(disconnect);
   
3. 
   pejorative prefixes, e.g. mis- (mispronounce); mal- (maltreat); pseudo- (pseudo-scientific);
   
4. 
   prefixes of time and order, e.g. fore- (foretell); pre- (pre-war); post- (post-war), ex- (ex-president);
   
5. 
   prefix of repetition: re- (rebuild, rewrite);
   
6. 
   locative prefixes, e.g. super- (superstructure), sub- (subway), inter- (inter-continental), trans- (transatlantic).
   

5. According to their stylistic reference prefixes fall into:

1. 
   those characterized by neutral stylistic reference, e.g. over-(oversee); under- (underestimate); un- (unknown);
   
2. 
   those possessing quite a definite stylistic value, e.g. pseudo-(pseudo-classical); super- (superstructure); ultra- (ultraviolet); uni-(unilateral); bi- (bifocal). These prefixes are of a literary-bookish character.
   

3. PRODUCTIVE AND NON-PRODUCTIVE AFFIXES

The word-forming activity of affixes may change in the course of time. This raises the question of productivity of derivational affixes, i.e. the ability of being used to form new, occasional or potential words, which can be readily understood by the language-speakers. Thus, productive affixes are those used to form new words in the period in question.

The most productive prefixes in Modern English are: de- (de­contaminate), re- (rethink), pre- (prefabricate), поп- (non-operational), un- (unfunny), anti- (antibiotic).
The most productive English suffixes are given below:

Noun-forming suffixes	-er (manager), -ing (fighting), -ness (sweetness), -ation (automation), -ее (evacuee), -ism (materialism), -ist (impressionist), -ance/-ancy (redundancy), -ry (gimmickry), -or (reactor), -ics (cybernetics)
Adjective-forming suffixes	-able (tolerable), -ic (electronic), -ish (smartish), -ed (learned), -less (jobless), -y (tweedy)
Verb-forming suffixes	-ize/-ise (vitaminize), -ate (oxidate), -ify (falsify)
Adverb-forming suffixes	-ly (equally)