Discipulus in via difficilius legit quam in bibliotheca.

Because discipulus is the subject, and Latin often puts the subject near the beginning. But Latin word order is much freer than English word order because the endings show each word’s role.

So Discipulus in via difficilius legit quam in bibliotheca could be rearranged in several ways without changing the basic meaning very much. The original order is just a natural way to say it.

Discipulus is nominative singular, which is the case normally used for the subject of the sentence.

You know it is the subject because:

• legit is a singular verb
• discipulus is a singular nominative noun
• the meaning fits: the student is the one doing the reading

The preposition in can take different cases depending on the meaning:

• in + ablative = in, on (location)
• in + accusative = into, onto (motion toward)

Here, via is in the ablative, so in via means in the road / on the road / in the street, not into the road.

Because via is a first-declension noun, and its nominative singular and ablative singular can look very similar in writing without macrons.

More exactly:

• nominative singular: via
• ablative singular: viā

In many beginner texts, macrons are omitted, so both appear simply as via. The preposition in tells you that this must be ablative here.

Difficilius is a comparative adverb, meaning more difficultly or more naturally in English, with more difficulty.

It is not describing a noun like via or discipulus. It is describing how the student reads, so it modifies the verb legit.

That is why the sentence means something like:

• The student reads with more difficulty on the road than in the library.

It is the comparative adverb related to difficilis (difficult).

A useful pattern is:

• adjective: difficilis = difficult
• adverb: difficulter = difficultly
• comparative adverb: difficilius = more difficultly

Latin often uses this -ius form for comparative adverbs.

Quam means than in comparisons.

So:

• difficilius ... quam ... = more difficultly ... than ...

The sentence compares two situations:

• reading in via
• reading in bibliotheca

Latin does not need to repeat the adverb or the verb in the second half. So quam in bibliotheca means than in the library, with the idea of reads understood.

Yes, you can think of the full idea as:

• Discipulus in via difficilius legit quam in bibliotheca legit.

or even:

• ... quam in bibliotheca difficilius legit is not the intended sense
• the meaning is really He reads more difficultly on the road than he does in the library

Latin often leaves out repeated words when they are easy to understand from context. This is very common.

Latin has no articles like English the and a/an.

So:

• discipulus can mean the student or a student
• via can mean the road or a road
• bibliotheca can mean the library or a library

The context or the English translation decides which is more natural.

It is ablative singular after in, just like via.

So:

• in via = in/on the road
• in bibliotheca = in the library

Again, with macrons:

• bibliothecā is the ablative singular

By itself, legit can mean either:

• he/she reads (present)
• he/she read (perfect)

This happens because some Latin verb forms look the same. You decide from context.

In a simple teaching sentence like this, legit is usually understood as reads.

Because difficilius is an adverb, and adverbs modify verbs, adjectives, or other adverbs—not nouns.

So it cannot mean the more difficult road here. If Latin wanted to describe the road, it would use an adjective agreeing with via, such as something like via difficilior.

Instead, difficilius legit means reads with more difficulty.

It is grammatically possible, but it sounds awkward in normal English. A more natural translation is:

• The student reads with more difficulty on the road than in the library.
• or The student finds it harder to read on the road than in the library.

Latin uses the adverb very naturally here, even if English prefers a different expression.

Yes. Depending on context, via can mean road, street, or way.

So in via might be translated:

• on the road
• in the street
• on the street

The best choice depends on the situation and on what sounds most natural in English.