Second Conjugation
The second conjugation is the -ē- family — every present-system form carries the long e you can hear: moneō, monēs, monet, monēmus, monētis, monent ("I warn, you warn…").
Sing that stem-vowel and the present, imperfect, and future click into place on the same endings every other verb uses.
The trap is the perfect. The default is -uī / -itum (moneō → monuī, monitum; habeō → habuī; terreō → terruī), but common verbs break the mold: videō → vīdī, vīsum; iubeō → iussī, iussum; maneō → mānsī; dēleō → dēlēvī, dēlētum.
You cannot guess perfects from the present — you memorize the four principal parts as a unit, the way English speakers learn "go, went, gone."
Spot the long ē in the infinitive (-ēre) — that flags 2nd conjugation. The default perfect is -uī / -itum, but several common verbs break the pattern.
Memorize all four principal parts as a chunk. Perfect-system formation is irregular by verb (moneō → monuī, videō → vīdī, iubeō → iussī, dēleō → dēlēvī) and cannot be predicted from the present.
| Case | 1 SG. | 2 SG. | 3 SG. | 1 PL. | 2 PL. | 3 PL. |
|---|---|---|---|---|---|---|
| Pres. Indic. | moneō | monēs | monet | monēmus | monētis | monent |
| Impf. Indic. | monēbam | monēbās | monēbat | monēbāmus | monēbātis | monēbant |
| Fut. Indic. | monēbō | monēbis | monēbit | monēbimus | monēbitis | monēbunt |
| Perf. Indic. | monuī | monuistī | monuit | monuimus | monuistis | monuērunt |
| Plup. Indic. | monueram | monuerās | monuerat | monuerāmus | monuerātis | monuerant |
| Fut. Perf. | monuerō | monueris | monuerit | monuerimus | monueritis | monuerint |
| Pres. Subj. | moneam | moneās | moneat | moneāmus | moneātis | moneant |
| Impf. Subj. | monērem | monērēs | monēret | monērēmus | monērētis | monērent |
| Perf. Subj. | monuerim | monueris | monuerit | monuerimus | monueritis | monuerint |
| Plup. Subj. | monuissem | monuissēs | monuisset | monuissēmus | monuissētis | monuissent |
| Case | 1 SG. | 2 SG. | 3 SG. | 1 PL. | 2 PL. | 3 PL. |
|---|---|---|---|---|---|---|
| Pres. Indic. | videō | vidēs | videt | vidēmus | vidētis | vident |
| Impf. Indic. | vidēbam | vidēbās | vidēbat | vidēbāmus | vidēbātis | vidēbant |
| Fut. Indic. | vidēbō | vidēbis | vidēbit | vidēbimus | vidēbitis | vidēbunt |
| Perf. Indic. | vīdī | vīdistī | vīdit | vīdimus | vīdistis | vīdērunt |
| Plup. Indic. | vīderam | vīderās | vīderat | vīderāmus | vīderātis | vīderant |
| Fut. Perf. | vīderō | vīderis | vīderit | vīderimus | vīderitis | vīderint |
| Pres. Subj. | videam | videās | videat | videāmus | videātis | videant |
| Impf. Subj. | vidērem | vidērēs | vidēret | vidērēmus | vidērētis | vidērent |
| Perf. Subj. | vīderim | vīderis | vīderit | vīderimus | vīderitis | vīderint |
| Plup. Subj. | vīdissem | vīdissēs | vīdisset | vīdissēmus | vīdissētis | vīdissent |
See It In Action
— B. G. v.48.5
Pure-pattern moneō in its native habitat: monet = "he advises," present-stem mone- + -t. Caesar uses moneō + ut + subjunctive constantly to report orders.
— Cic. Cat. i.13
Iubet looks like a textbook 2nd-conj. present (same shape as monet), but its perfect is iussit, not iubuit — one of the verbs you simply have to memorize.
— B. G. i.49.2
Same verb, perfect tense: iussit = "he ordered." The doubled -ss- and the lost root -b- are the giveaway that you're in the perfect, not the present.
— Verg. Aen. xi.40
Vidit is the perfect of videō: stem vīd- + -it. Compare the present videt ("he sees") — only the macron and the missing -e- mark the tense, and Latin manuscripts often drop the macron.
Most 2nd-conj. perfects use -uī / -itum, but a stubborn minority of common verbs sharpen, contract, or lengthen — there's no rule, only memorization.
the regular pattern; about two-thirds of 2nd-conj. verbs
moneō → monuī, monitum
warn / warned / having been warned
sigmatic -sī, lengthened root, or -vī
videō → vīdī, vīsum · iubeō → iussī, iussum · dēleō → dēlēvī, dēlētum
see / saw / seen · order / ordered / ordered · destroy / destroyed / destroyed
Tip: Ask: do I actually KNOW the third principal part of this verb? If you're guessing -uī, stop and look it up — videō, iubeō, maneō, augeō, dēleō, sedeō, ārdeō are the famous traps.
Caesar writes castra munire iussit (B. G. i.49.2). What tense and verb is iussit?
Study Tips
- •Listen for the long ē in the present system — monēs, monet, monēmus, monētis, monent. If you can hum the stem-vowel, the endings are the same as every other verb.
- •Memorize all four principal parts together (moneō, monēre, monuī, monitum) — the perfect and supine stems are unpredictable from the present, and you need them for every perfect-system tense and every participle.
- •Drill videō → vīdī and iubeō → iussī alongside moneō → monuī. Realizing that 2nd-conjugation perfects come in three flavors (-uī, sigmatic -sī, lengthened -vī) prevents the panic-misparse later.
- •When you see a verb in -ēre (long e), you are in the second conjugation. -ere (short e) is the third — the macron is the difference between monēre ("to warn") and legere ("to read").