Quamvis pluvia gravis cadat, plerique discipuli lectioni intersunt.

Quamvis means although or even though. It introduces a concessive clause, meaning a clause that presents a fact or circumstance that does not prevent the main action from happening.

So in this sentence:

Quamvis pluvia gravis cadat, plerique discipuli lectioni intersunt.

the first part means Although heavy rain is falling and the main clause says most of the students are attending the lesson.

The idea is: the rain might be expected to keep them away, yet they still come.

After quamvis, Latin normally uses the subjunctive.

So:

• cadit = it falls / is falling (indicative)
• cadat = present subjunctive

In a clause with quamvis, the subjunctive does not necessarily make the action doubtful. It is mostly there because the construction requires it.

So quamvis pluvia gravis cadat simply means although heavy rain is falling, not although heavy rain may be falling in any especially uncertain sense.

Cadat is present subjunctive, active, 3rd person singular, from cado, cadere = to fall.

Because the sentence is talking about something happening at the same time as the main clause, English will usually translate it with a present idea such as:

• although heavy rain is falling
• although heavy rain falls

In natural English, is falling is often the best choice here.

Pluvia gravis is nominative singular:

• pluvia = rain
• gravis = heavy

It is nominative because it is the subject of cadat.

So literally:

• pluvia = rain
• gravis = heavy
• cadat = falls / is falling

Latin adjectives agree with their nouns in gender, number, and case, so gravis matches pluvia.

Plerique means most, most people, or the majority.

Here it agrees with discipuli, so:

• plerique discipuli = most of the students

A useful thing to notice is that plerique often appears mainly in the plural, because the idea of most usually refers to a group.

Because intersum takes the dative, not the accusative.

• intersum, interesse, interfui = to be present at, to take part in, to attend

So:

• lectioni = to/at the lesson (dative singular)

That is why Latin says:

• lectioni intersunt = they are present at the lesson / they attend the lesson

This is a very common point of confusion for English speakers, because English uses attend + direct object, but Latin uses intersum + dative.

Intersunt comes from intersum, which is a compound of inter + sum.

It is parsed as:

• intersunt = they are present / they attend
• 3rd person plural, present indicative active

Because it comes from sum, its forms resemble forms of to be:

• intersum = I am present
• interes = you are present
• interest = he/she/it is present
• intersumus = we are present
• interestis = you all are present
• intersunt = they are present

Discipuli is nominative plural because it is the subject of intersunt.

The main clause is:

plerique discipuli lectioni intersunt

which breaks down as:

• plerique discipuli = most of the students — subject
• lectioni = at the lesson — dative with intersunt
• intersunt = are present / attend

So discipuli must be nominative plural to match the plural verb intersunt.

Yes, but in a normal Latin way.

Latin word order is more flexible than English because the endings show the grammatical relationships. This sentence puts the concessive clause first:

Quamvis pluvia gravis cadat, ... = Although heavy rain is falling, ...

Then comes the main clause:

plerique discipuli lectioni intersunt. = most of the students attend the lesson.

A few things to notice:

• placing quamvis first clearly signals the concessive idea
• putting plerique discipuli before lectioni intersunt highlights most of the students
• ending with intersunt is very natural in Latin, since verbs often come last

So the word order is not strange; it is a normal and readable Latin arrangement.

In standard classical Latin, quamvis meaning although is regularly followed by the subjunctive.

So in a sentence like this, a learner should expect:

• quamvis ... cadat, not quamvis ... cadit

There are a few historical and stylistic complications in Latin literature, but for learning purposes the important rule is simple:

• quamvis
  • subjunctive = although / even though

The sentence has two parts:

1. Quamvis pluvia gravis cadat

   • concessive subordinate clause
   • Although heavy rain is falling

2. plerique discipuli lectioni intersunt

   • main clause
   • most of the students attend the lesson

So the full structure is:

Although X is happening, Y still happens.

That pattern is very common in Latin and worth recognizing quickly when you see quamvis.