Invariable words have ordered and regular series of grammatically different forms.

A derivational affix serves to derive a new word when it is added to another morpheme.

Grammatical words express grammatical meanings; conjunctions, prep, articles, and pronouns.

Open class words are mostly variable words.

Flu is formed by utting both the initial and final parts of the word influenza accordingly, this type of word formation is called

Aids is formed by joining the initial letters of the phrase acquired immune deficiency syndrome, this tpye of word formation is called .

______ is a reverse process of derivation, and therefore is a process of shortening.

The stem of disagreements is _____.

The words like comsat and sitcom are formed by ______.

Lexicon, in most cases, is synonymous with ___.

Cold and hot are a pair of _____ antonyms.