Grammatica Capitulum XXXI · Inter pōcula

The central point is the gerundive in -ndus. It looks like the gerund from capitulum XXVI, but behaves very differently: it accompanies a noun, agrees with it and, when joined to esse, expresses what must be done.

1. A form that agrees

The stem is the present stem. Fourth-conjugation and mixed verbs keep their i: audiendus, faciendus.

2. With esse: what must be done

• Lēx servanda est: the law must be observed.
• Scelus pūniendum est: the crime must be punished.
• Verba scrībenda sunt: the words must be written.

The form does not place the action in the future. It expresses necessity, obligation or what is fitting to do.

3. The person responsible for acting

In Liber discipulō legendus est, discipulō names the person to whom the reading falls: “the book must be read by the pupil.” That person is in the dative. Look for two elements separately:

1. the thing that must undergo the action;
2. the person to whom that action falls.

4. The use without a noun

The neuter singular can stand alone:

• Tacendum est: one must be silent.
• Dēspērandum nōn est: one must not despair.
• Bibendum nōn est: one must not drink.

The sentence then names no particular person or thing.

5. Gerundive or gerund?

• ars scrībendī: the gerund names the action of writing and remains neuter singular.
• epistula scrībenda: the gerundive accompanies epistula and takes its feminine form.

Agreement is the safest test: if the word in -nd- changes with a noun, it is the gerundive.

6. Two special families

Fīdere and cōnfīdere are semi-deponent: active present (fīdō), perfect built with an active-sense participle (fīsus sum).

Quisquis means “whoever” and quidquid “whatever.” The reduplication applies to both halves of the pronoun.

Remember

1. -ndus, -nda, -ndum agrees like bonus.
2. With esse, the form expresses what must be done.
3. The responsible person is put in the dative.
4. The neuter singular without a noun gives a general obligation.
5. The gerund does not agree; the gerundive does.