Latin Reference — Vol. IV.a: Verbs That Lean on Verbs
The first syntax in the library. Everything before this was morphology — how a single word changes shape (declines, conjugates). This volume is about how words join: a verb that needs a second verb to complete its meaning. It sits after Vol. IV because it depends on the infinitive — the to — form — which the verb engine introduces.
It begins, like so much here, with a weasel: Mustelae mūrēs coquere nōn solent — the weasels do not usually cook mice. Where does “usually” come from? From a verb that means “to usually-do”.
soleō — a verb meaning “to be in the habit of”
soleō, solēre = to be accustomed to, to be in the habit of. The habituality is lexical — baked into the word — not added by a tense or an adverb. English has no single verb for this, so translations smuggle it in as “usually” or “tend to”.
mūrēs coquere nōn solent — literally they-are-not-accustomed to-cook mice → “they don’t usually cook mice”.
The “usually” is solent. Everything English spreads across an adverb, Latin packs into one verb — the same compression you met with the frequentatives in Vol. VII, but here it drives a whole construction.
The complementary infinitive
Notice solent doesn’t work alone — it needs coquere (to cook) to complete the thought. A verb that requires a second verb in the infinitive to finish its meaning takes what’s called a complementary infinitive (it completes — complement, not compliment).
The machinery:
- The main verb is finite — it carries the person and number (solent = they, -nt).
- The infinitive hangs off it, uninflected, naming the action (coquere = to cook).
- Negation and objects slot around them: mūrēs (object, acc pl) + coquere + nōn solent.
So the sentence frame is: [subject] [object] [infinitive] [main verb] — “weasels, mice, to-cook, are-not-accustomed”. Latin happily stacks the infinitive before its main verb; read to the finite verb to find who’s doing it.
The little club
soleō belongs to a small, very common family of verbs that all take a complementary infinitive. Learn the set and you’ll expect an infinitive nearby whenever one appears:
| Verb | Means | Example | Translation |
|---|---|---|---|
| soleō, solēre | be accustomed to | legere soleō | I usually read |
| possum, posse | be able to, can | legere possum | I am able to read / I can read |
| dēbeō, dēbēre | ought to, must, owe | venīre dēbēs | you ought to come |
| volō, velle | want to | venīre volunt | they want to come |
| nōlō, nōlle | not want to, refuse | pugnāre nōlunt | they refuse to fight |
| cōnstituō | decide to | manēre cōnstituit | he decided to stay |
| audeō, audēre | dare to | intrāre audet | she dares to enter |
| incipiō | begin to | labōrāre incipit | he begins to work |
Aside — possum, already met. You half-knew this construction before naming it. possum (“I am able”) is the workhorse of the club: legere possum, “I can read”. It’s irregular (a fusion of pot- “able” + sum “I am” — literally “I am able”), but it slots an infinitive on exactly like soleō. The pattern was hiding in a verb you’d already seen.
Worked sentences
| Latin | Translation | Mechanics |
|---|---|---|
| Mustelae mūrēs coquere nōn solent. | Weasels do not usually cook mice. | solent (they, habitual) + coquere (compl. inf.); mūrēs acc obj |
| In templō ōrāre solēbant. | They used to pray in the temple. | solēbam imperfect (Vol. VII) — habit in the past |
| Latīnē legere iam possum. | I can already read Latin. | possum + legere; Latīnē = adverb, “in Latin” |
| Mīlitēs fortiter pugnāre dēbent. | Soldiers ought to fight bravely. | dēbent + pugnāre; fortiter adverb |
| Discēdere nōn audet. | He does not dare to leave. | audet + discēdere; nōn negates the daring |
Note the second example: solēbant is soleō in the imperfect — “they were in the habit of”, habit pushed into the past. The construction and the tense system stack cleanly, as systems built from the same parts tend to.
The momentary trap in the weasel sentence
Mustelae is a Vol. III.c ambush: it could be genitive singular (“the weasel’s”) or nominative plural (“the weasels”). What settles it? The verb. solent is third-person plural (-nt), so it demands plural subjects — weasels, nominative. The ending outvotes the ambiguity, precisely the resolution strategy III.c set out. And nōn parks directly before what it negates (the III.a particle rule). Three volumes’ worth of machinery, quietly cooperating in one cartoon about weasels declining to cook.
Aside — insolent. soleō surfaces in English as insolent — in- (not) + solēns (accustomed) = “unaccustomed”, hence not knowing one’s accustomed place, hence rude. Also obsolete — ob- + solēre, fallen out of the habit of being used. The weasel sentence teaches a verb you already carry around as an insult.
The drill
Take the little club and pair each verb with an infinitive you know, in the third person singular and plural: legere solet / solent, venīre dēbet / dēbent, pugnāre audet / audent. Then negate one and give it an object — mūrēs coquere nōn solent. The aim is to stop seeing two verbs and start seeing one idea: “are-accustomed-to-cook” as a single unit with the person on the end. When the infinitive stops looking like a second verb and starts looking like the completion of the first, the construction is yours.