Question re pronunciation, interficere:
Here, the pronunciation sounds like "interFIcimus" (stress on the third syllable). In a different sentence, the pronunciation is "inTERficit" (stress on the second syllable). Is there a reason for this difference? If so, what is the reason?
Latin stress is based on the 'weight' of the penultimate syllable. I will briefly explain, someone please improve my answer should it be lacking.
If the penultimate is closed (ends with a consonant), long, or a diphthong, then the penultimate is heavy and the stress is on the penultimate. Otherwise, it is on the ante-penultimate.
None of the vowels in either word are long (interficere is a thrid-io conjugation).
in-ter-FI-ci-mus -> since ci is not heavy the stress lands on the ante-penultimate fi.
in-TER-fi-cit -> since fi is not heavy the stress lands on the anti-penultimate ter.
Link to some links that probably better explain this: