Nunc mater rogat utrum per pontem an per vadum ad agrum aviae eamus.

It introduces an either/or question: whether ... or.

So:

• utrum per pontem
• an per vadum

means whether by the bridge or by the ford.

This is a very common Latin way to set up two alternatives.

Because the sentence contains an indirect question after rogat.

Latin normally uses the subjunctive in indirect questions. After a verb like rogat (asks), the embedded question takes a subjunctive verb:

• direct question: Eamusne per pontem an per vadum?
• indirect question: mater rogat utrum per pontem an per vadum eamus

So eamus is not a command here; it is the normal verb form for the reported question.

Because rogat is present tense, Latin usually follows primary sequence, so the indirect question takes the present subjunctive when the action is simultaneous with or later than the main verb.

So:

• rogat = she is asking
• eamus = whether we should go / are to go / go

If the main verb were past, Latin would often use the imperfect subjunctive instead.

Because the ending of the verb already tells you the subject.

In eamus, the ending -mus shows first person plural: we.

Latin often leaves subject pronouns out unless they are needed for emphasis or contrast.

Because per takes the accusative.

So:

• per pontem = across/through the bridge
• per vadum = through/by way of the ford

Whenever you see per, expect the following noun to be accusative.

Because it follows ad, and ad also takes the accusative when it means movement to or toward a place.

So:

• ad agrum = to the field

That is different from a location expression like in agro, which would mean in the field.

Because it shows possession: the grandmother’s field or the field of the grandmother.

So:

• agrum aviae = the grandmother’s field

The form aviae can have more than one possible grammatical value in Latin, but here the meaning and syntax show that it is genitive singular.

Latin often repeats the preposition with each alternative for clarity:

• per pontem
• an per vadum

English can sometimes omit the second preposition, but Latin very naturally repeats it, especially in a balanced either/or structure like this one.

A vadum is a ford: a shallow place in a river or stream where you can cross through the water.

So the contrast is:

• per pontem = by the bridge
• per vadum = by the ford

It is not another kind of bridge; it is a water crossing without a bridge.

Because Latin has no articles.

So mater can mean mother, the mother, or sometimes a mother, depending on context. The same is true for pontem, vadum, agrum, and aviae.

English has to choose an article, but Latin usually leaves that to context.

The word order is flexible, but it is not random.

A few useful points:

• Nunc comes first to set the scene: now
• mater rogat gives the main statement early: mother asks
• utrum ... an neatly presents the two alternatives
• ad agrum aviae comes after them because it belongs with the whole idea of going
• eamus comes at the end, which is very common in subordinate clauses

So Latin word order often helps group ideas, even though the case endings do most of the grammatical work.