Teachers can,
and good ones often do,
teach for example indefinite pronouns, demonstrative pronouns, relative pronouns, and other groupings with as much fervor and
authority as some others myopically, and with intensity, present the narrow, self-focused, intrinsically, inwardly aware group of words in place of nouns, of what are known and currently popular as a collective "expertise" in Personal Pronouns.
Such is ones pleasure trove.