Hostes regnum oppugnare volunt, sed cives et milites id defendunt.

Because volunt is a verb of wanting, and after it Latin normally uses an infinitive.

• volunt = they want
• oppugnare = to attack / to assail

So Hostes regnum oppugnare volunt literally means The enemies want to attack the kingdom.

This is a very common Latin pattern:

• puer currere vult = the boy wants to run
• milites pugnare volunt = the soldiers want to fight

So oppugnare is not the main verb of the clause by itself; it depends on volunt.

Here hostes is nominative plural, so it is the subject of volunt.

The noun is hostis, hostis = enemy. In the plural:

• hostes can be nominative plural = enemies
• or accusative plural = enemies

So how do we know which it is here? From the sentence structure:

• volunt is a plural verb, so it needs a plural subject.
• hostes fits naturally as that subject.
• regnum is singular and clearly works as the object of oppugnare.

So here hostes means the enemies.

Regnum is in the accusative singular, because it is the direct object of oppugnare.

The noun is regnum, regni = kingdom. It is a neuter second-declension noun. For neuter second-declension nouns:

• nominative singular = regnum
• accusative singular = regnum

So the form looks the same in both cases. You tell its role from the syntax:

• hostes = subject
• regnum = thing being attacked

That is why regnum means the kingdom as the object here.

Volunt is the 3rd person plural present active indicative of velle, meaning to want.

So volunt means:

• they want

Its singular form is vult = he/she/it wants.

A few useful forms of velle are:

• volo = I want
• vis = you want
• vult = he/she/it wants
• volumus = we want
• vultis = you all want
• volunt = they want

So in this sentence, hostes ... volunt = the enemies want ...

Id is a pronoun meaning it, and here it refers back to regnum.

This is common in Latin, just as in English. Instead of saying:

• ... sed cives et milites regnum defendunt

the sentence says:

• ... sed cives et milites id defendunt

That avoids repetition.

Grammatically, id is:

• accusative singular neuter
• from the pronoun is, ea, id

It must be neuter singular because it refers to regnum, which is a neuter singular noun.

Because it refers to regnum, and regnum is a neuter noun.

In Latin, pronouns usually agree with the noun they refer to in gender and number. Since regnum is:

• singular
• neuter

the pronoun must also be singular neuter:

• id = it

So the grammar is:

• regnum = neuter singular noun
• id = neuter singular pronoun referring back to it

Because its subject is cives et milites = citizens and soldiers, which is a compound plural subject.

Even though there are two nouns, together they act as one plural subject:

• cives = citizens
• et = and
• milites = soldiers

So the verb must be plural:

• defendunt = they defend

If the subject were singular, the verb would also be singular. For example:

• civis id defendit = the citizen defends it

Both are nominative plural here, because they are the subjects of defendunt.

• cives comes from civis, civis = citizen
• milites comes from miles, militis = soldier

In this sentence they are joined by et and together form the subject:

• cives et milites id defendunt
• the citizens and soldiers defend it

Like hostes, these forms can sometimes also be accusative plural in other contexts, but here the verb makes their function clear.

Latin word order is much more flexible than English word order because the endings show the grammatical relationships.

So this sentence could be rearranged in several ways without changing the basic meaning, for example:

• Hostes volunt regnum oppugnare, sed cives et milites id defendunt.
• Regnum hostes oppugnare volunt, sed id cives et milites defendunt.

However, word order still affects emphasis and style. The given order is natural and clear:

• Hostes comes first, introducing the first group.
• regnum appears before oppugnare, keeping object and infinitive close.
• sed marks the contrast.
• cives et milites comes before defendunt, highlighting the defenders.

So the order is not rigid, but it is meaningful.

Because Latin has no definite article and no indefinite article.

So Latin does not have separate words for:

• the
• a
• an

A noun like hostes can mean:

• enemies
• the enemies

and regnum can mean:

• a kingdom
• the kingdom

You decide from the context which English article is best. In this sentence, English naturally uses the:

• The enemies want to attack the kingdom, but the citizens and soldiers defend it.

Sed means but and introduces a contrast between the two clauses.

The sentence sets up an opposition:

• Hostes regnum oppugnare volunt = the enemies want to attack the kingdom
• sed cives et milites id defendunt = but the citizens and soldiers defend it

So sed signals that the second clause goes against or responds to the first.

Yes. Latin could say:

• sed cives et milites regnum defendunt

That would still mean but the citizens and soldiers defend the kingdom.

Using id instead is simply a smoother way to refer back to something already mentioned. English often does the same:

• They attack the kingdom, but the citizens defend it instead of
• They attack the kingdom, but the citizens defend the kingdom

So id is not required, but it is a natural and elegant choice.

The two main finite verbs are:

• volunt = they want
• defendunt = they defend

These are the verbs that are fully conjugated and anchor the two clauses.

The full structure is:

1. Hostes regnum oppugnare volunt

   • main verb: volunt
   • infinitive depending on it: oppugnare

2. sed cives et milites id defendunt

   • main verb: defendunt

So oppugnare is verbal, but it is not a main finite verb like volunt and defendunt.