The Word Families
All the words in the English language belong to one or another of nine
families, each of which family has a special duty. If you will always
remember to which family a word belongs and just what that family does,
you will be saved from many very common errors. These nine families
are:1, nouns; 2, adjectives; 3, articles; 4, verbs; 5, pronouns; 6,
adverbs; 7, prepositions; 8, conjunctions; 9, interjections. This order
of enumeration is not exactly the same as will be found in the grammars.
It is used here because it indicates roughly the order of the appearance
of the nine families in the logical development of language. Some forms
of interjections, however, may very probably have preceded any language properly so called.