I was reading Plautus and came across quacum, which set in motion a few observations:
Most beginning Latinists are familiar with the following constructions with first- and second- person and reflexive pronouns, which usage seems to mandate in all cases.
- cum + te = tecum
- cum + nobis = nobiscum, etc.
- idem for se, vobis, and me
Other constructions (according to my cursory research) appear to be optional. I have seen this especially with relative pronouns:
- cum + qua = quacum or cum qua
- cum + quibus = quibuscum or cum quibus
Everything else seems simply forbidden:
- cum + Marco =/= Marcocum
- cum + filio =/= filiocum
- cum + eo =/= eocum
I have a few related questions:
- Are there good counterexamples where cum + personal pronoun is not combined, e.g. cum te?
- Are there examples of cum being added at the end of a word not in the first or second category?
- Is there any difference between cum qua and quacum?
Let me know if this seems too broad.