Hospes rogat cur amphora tam cito vacua facta sit, et caupo dicit vinum hodie deesse.

Because it’s an indirect question introduced by rogat (he asks). In Latin, indirect questions normally take the subjunctive. So:

• rogat cur ... sit = he asks why ... is/was ...
• cur is the question word (why), and that triggers the indirect-question construction with the subjunctive.

facta sit is perfect subjunctive passive (3rd person singular).

• facta = perfect passive participle (having been made / having become)
• sit = subjunctive of esse

The perfect here suggests the emptying happened before (or is viewed as completed relative to) the asking: “why it has become empty so quickly.”

Because this clause is an indirect question, not an indirect statement.

• Indirect questions use a finite verb in the subjunctive: cur ... facta sit
• Indirect statements use accusative + infinitive: e.g. dicit amphoram vacuam factam esse (he says that the jar has become empty)

So rogat → indirect question → subjunctive.

In an indirect question, the clause keeps normal subject marking, so amphora is the subject of facta sit and stays nominative.

The accusative subject pattern (amphoram ... esse) belongs to indirect statements, not indirect questions.

vacua and facta both agree with amphora in gender, number, and case:

• amphora = feminine, singular, nominative
• vacua = feminine, singular, nominative
• facta = feminine, singular, nominative

So it literally reads: “the jar (f.) empty (f.) having-been-made / having-become (f.)”.

It’s slightly different in focus.

• vacua sit = “is empty” (state)
• vacua facta sit = “has become empty / was made empty” (change into that state)

Latin often uses factus + adjective to express becoming: factus iratus = became angry, etc.

tam = so (degree adverb)
cito = quickly
Together tam cito = so quickly

It modifies the whole idea of becoming empty: “why the jar became empty so quickly.”

That’s an indirect statement after dicit:

• vinum (accusative) = subject of the indirect statement
• deesse (infinitive) = verb of the indirect statement

So: dicit [vinum] [deesse] = “he says that wine is lacking.”

Because in Latin indirect statement, the logical subject becomes accusative (the accusative-and-infinitive construction):

• direct: vinum deest = wine is lacking
• indirect: dicit vinum deesse = he says that wine is lacking

So vinum is accusative because it’s the subject of deesse inside indirect speech.

The present infinitive in indirect statement typically shows an action/state contemporaneous with the main verb (dicit). Since he is speaking now, deesse naturally means “to be lacking (now/today).”

If the lack were earlier, Latin might use a perfect infinitive (where available) or rephrase, but here the sense is simply: “today there isn’t any wine.”

Both are nominative singular subjects:

• hospes = guest (3rd declension noun; nominative = hospes)
• caupo = innkeeper / tavern-keeper (3rd declension noun; nominative = caupo)

So the sentence has two main verbs with their subjects:

• Hospes rogat ...
• caupo dicit ...