Quisque discipulus codicem suum legit.

Because quisque means each and treats the group one person at a time. Latin handles that idea with the singular, not the plural.

So:

• quisque = each
• discipulus = student, singular
• suum = his own / their own, singular to match the thing possessed
• legit = he/she reads, singular

Even if many students are meant overall, Latin is viewing them individually.

Discipulus is nominative singular. The nominative case is the usual case for the subject of the sentence.

We know it is the subject because:

• it is in the nominative form
• legit is third person singular, so it matches a singular subject
• semantically, the student is the one doing the reading

So discipulus is the one who reads.

Codicem is accusative singular, the case used for the direct object.

It is the direct object because it is the thing being read. The verb legit takes an object, and codicem is that object.

Its dictionary form is codex. This is a third-declension noun, so the forms can look quite different:

• nominative singular: codex
• genitive singular: codicis
• accusative singular: codicem

So codicem means the book / the codex as the object of the verb.

Because suum is the reflexive possessive. It refers back to the subject of the clause.

So here, suum means that each student reads his own book.

If Latin used eius instead, the meaning would normally be his/her book referring to someone else, not back to the subject. That would weaken or remove the idea of one's own.

So:

• suum = his/her/their own, referring back to the subject
• eius = his/her, usually referring to someone else

Because Latin possessive adjectives agree with the thing possessed, not with the possessor.

Here the possessed thing is codicem, which is:

• masculine
• singular
• accusative

So the possessive adjective must also be:

• masculine
• singular
• accusative

That gives suum.

Even though the owner is discipulus, the form of suum is determined by codicem.

Legit is third person singular from legere, meaning to read.

In this sentence, it is naturally understood as reads or is reading, depending on context. Latin present tense often covers both simple present and progressive ideas that English separates.

So legit can correspond to:

• reads
• is reading

Yes. In writing, legit can be ambiguous, because it can represent either:

• present: reads
• perfect: read / has read

In Classical Latin, vowel length helped distinguish these in pronunciation, but many printed texts for learners do not mark that consistently, and ordinary spelling does not show the difference clearly.

So you usually rely on context to tell which tense is meant. In this sentence, if the meaning shown to the learner is present, then that is the reading to take.

Latin word order is more flexible than English word order because the endings show what each word is doing.

This sentence uses a very straightforward order:

• subject: quisque discipulus
• object: codicem suum
• verb: legit

That is a common and natural Latin pattern. But Latin could rearrange the words for emphasis without changing the basic meaning, for example:

• Codicem suum quisque discipulus legit
• Quisque discipulus suum codicem legit

The endings still show who is doing the action and what is being read.

Because Latin has no articles. It does not have separate words that exactly match English the, a, or an.

So a noun like discipulus can mean, depending on context:

• a student
• the student
• simply student

Likewise codicem could be translated as a book, the book, or just book, depending on what sounds natural in English and what the context requires.

By itself, suum does not tell you the natural gender of the possessor. It is a reflexive possessive meaning one's own, and its form changes to match the possessed noun, not the owner.

So in different contexts, forms of suus can be translated as:

• his own
• her own
• their own

In this sentence, because discipulus is grammatically masculine singular, English will normally give his own. But the core grammatical idea is simply the subject's own.