In the fortieth class of the Latin from Scratch course, we’ll study the most frequent compounds of the verb sum, which are formed by the addition of a preverb to add shades or change the meaning of sum.
I explain everything in the following video (⏳ 07m 53s ⌛):
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Most frequent compounds of sum
Each verb can potentially have as many compounds as there are preverbs, and this is the case with sum, but we are going to study (and learn by heart) the most important compounds of sum only.
They are the following:
- absum “be away (from)”, “be far (from)”
- adsum “be present”, “attend”
- possum “can” (+ infinitive)
- praesum “preside over”, “lead”, “be in charge” (+ dative)
- prosum “be useful”, “favor”, “help”
- supersum “survive”, “remain” (as in ‘has not disappeared, died, etc.’)
All of these verbs are intransitive (except for possum, which has a nominal → direct object infinitive).
Irregularities
Most of these verbs are conjugated exactly the same as sum (with the preverb), but two of them, prosum and possum, have special irregularities.
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prosum
The irregularity in the verb prosum lies in the preverb, which can appear as pro‑ and prod‑ in the following distribution:
- pro‑ when followed by a consonant (e.g. prosum)
- prod‑ when followed by a vowel (e.g. proderam)
possum
Although there are similarities in the distribution of the irregularities, there is more to it:
- pos‑ when followed by a consonant (e.g. possum)
- pot‑ when followed by a vowel (e.g. poteram)
Apart from the variation in the preverb, there are some more irregularities:
- the present infinitive undergoes a simplification (*po
tesse > posse), which also affects the imperfect subjunctive: *potessem > possem; *potesses > posses… - the perfect stem loses the f, which makes it potu‑, not *posfu‑ (e.g. *pos
fueram > *posueram > potueram)
After the compounds of the verb sum and their irregularities, let’s study, in the next class, the most frequent irregular verbs.
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