Methodological typology

Dif. words require dif. treatment. There were some attempts to create some methodological typology of words e.g. Charles Frees in his book The Structure of English' distinguished 4 types of words acc.to their functions in the sentence and combinability:

1)Form words e.g. will, shall, do, did, does, etc.

2)Words-substitutes e.g. he, she, one, etc.

3)Content words denoting things, constitute the bulk of the Voc.;

4)Grammatically distributive words e.g. some, any, etc.