> Hidden inside WWB (writer's workbench), Lorinda Cherry's Parts annotated English text with parts of speech, based on only a smidgen of English vocabulary, orthography, and grammar.
Writer's Workbench was indeed a marvel of 1970's limited-space engineering. You can see it for yourself [1]: the generic part-of-speech rules are in end.l, the exceptions in edict.c and ydict.c, and the part-of-speech disambiguator in pscan.c. Such compact, rule-based NLP has fallen out of favor these days but (shameless plug alert!) Writer's Workbench inspired my 2018 IOCCC entry that highlights passive constructions in English texts [2].
[1] https://github.com/dspinellis/unix-history-repo/tree/BSD-4_1...