According to the role they play in constructing words, morphemes are subdivided into roots and affixes. .................................................................................................................... into prefixes, suffixes and infixes

.......................................... exist in language and are reproduced in speech as ready-made units, whereas free word groups or combinations are created in speech every time we need them.

Antonyms are words of the same part of speech, but opposite in meaning. Many words, especially those denoting concrete objects (chair, tree, tiger) have no antonyms. Usually adjectives denoting qualities, verbs ............................. actions or state and abstract nouns have antonyms

...................................................., some prefixes express the difference between a transitive and an intransitive verb: stay v and outstay (smb) v t. With a few exceptions prefixes modify the stem for time (pre-, post-), place (in-, ad-), negation (un-, dis-) and remain semantically rather independent of the stem

Derivational suffixes ................... of the original word: they may change the word class, specify the word or generalise it. Most scholars recognise suffixes forming nouns, verbs, adjectives and adverbs