Amici sortiuntur, et sors primum lusorem eligit.

Because sortior is a deponent verb.

In Latin, deponent verbs use passive forms but have an active meaning. So:

• sortior = I draw lots / I obtain by lot
• sortiuntur = they draw lots

Even though -untur is a passive-looking ending, here it does not mean they are drawn by lot. It means they draw lots.

This is a very common thing for Latin learners to notice and ask about.

Sortiuntur is:

• 3rd person plural
• present tense
• indicative mood
• from the deponent verb sortior, sortiri

So it means they draw lots or they are drawing lots, depending on context.

Because amici is the subject of sortiuntur.

• amici = friends
• nominative plural of amicus

Since the verb means they draw lots, we ask: who is drawing lots?
Answer: the friends.

So amici must be in the nominative, the case normally used for the subject.

Yes. They are closely related in meaning.

• sors = lot, chance, a lot used for drawing
• sortior = to draw lots, to obtain by lot

So the sentence uses both the verb and the noun from the same basic idea:

• Amici sortiuntur = the friends draw lots
• sors ... eligit = the lot chooses/selects

This is a neat bit of Latin word-family vocabulary.

Sors is nominative singular.

It is the subject of the second verb, eligit:

• sors = the lot
• eligit = chooses/selects

So in the second clause, the thing doing the action is sors, which is why it is nominative.

Primum lusorem is accusative singular because it is the direct object of eligit.

• eligit = chooses / selects
• Whom does the lot choose?
• primum lusorem = the first player

Both words are accusative singular:

• primum modifies lusorem
• lusorem is accusative singular of lusor

So the phrase means the first player.

Because primum here is an adjective, not an adverb.

It agrees with lusorem in:

• case: accusative
• number: singular
• gender: masculine

So:

• primum lusorem = the first player

If it were an adverb, primum could mean at first or first in a different sense, but here it is clearly describing lusorem.

Because the friends are all taking part in the lot-drawing, but the lot selects only one person as the first player.

So the sentence means:

• several friends draw lots
• the lot chooses one first player

That is why:

• amici = plural
• lusorem = singular

This is a natural way of speaking in both Latin and English.

It is a kind of shorthand or personification:

• literally, the lot chooses
• in sense, the outcome of the lot determines who goes first

Latin often allows this kind of expression. It does not mean the lot is alive; it just means the decision is made by lot.

Because its subject, sors, is singular.

In the second clause:

• sors = singular subject
• eligit = he/she/it chooses, 3rd person singular present

If the subject were plural, the verb would also be plural. But here there is only one sors.

Both verbs are in the present tense:

• sortiuntur = they draw lots / are drawing lots
• eligit = chooses / is choosing

Latin present tense can often be translated in more than one way in English, depending on context:

• Friends draw lots, and the lot chooses the first player
• The friends are drawing lots, and the lot is choosing the first player

Both are possible as translations of the grammar.

Not really. It is perfectly normal Latin word order.

The sentence is:

• Amici sortiuntur
• et sors primum lusorem eligit

Latin word order is more flexible than English because endings show the grammatical roles. So Latin does not rely as heavily on position.

This sentence is fairly clear and straightforward:

• subject + verb
• et
• subject + object + verb

Also, Latin often likes to place the main verb toward the end of a clause, as in eligit.

Et simply means and.

It joins the two clauses:

• Amici sortiuntur
• sors primum lusorem eligit

So the whole sentence gives a sequence:

1. the friends draw lots
2. the lot selects the first player

The dictionary form is lusor.

More fully, you might see:

• lusor, lusoris = player

In the sentence, it appears as lusorem, which is the accusative singular form.

A learner often needs to get used to the fact that Latin dictionary entries usually give the nominative singular, while the sentence may use a different form.

Yes, the verb sortior can have meanings like:

• draw lots
• decide by lot
• obtain by lot

Which English wording is best depends on context.

In this sentence, because the next clause mentions sors choosing the first player, the most natural understanding is that the friends are drawing lots to decide who goes first.