Si tingués més temps aquesta tarda, repassaria els apunts abans de sopar.

Because this sentence is expressing a hypothetical / unreal condition: If I had more time... In Catalan, a common pattern for this is:

si + imperfect subjunctive → conditional

So here:

• Si tingués més temps... = If I had more time...
• ...repassaria els apunts... = ...I would review the notes...

The verb tingués is the imperfect subjunctive of tenir.

Because it is the result of the hypothetical condition.

The sentence follows this structure:

• Si tingués... = If I had...
• repassaria... = I would review...

So repassaria is the conditional form of repassar. It matches English would review.

This is the normal pairing in Catalan for this kind of sentence:

• Si + imperfect subjunctive
• conditional

Because tindria is a conditional form, and Catalan does not normally use the conditional after si in this type of clause.

So:

• Correct: Si tingués més temps, repassaria...
• Not standard here: Si tindria més temps...

A useful shortcut is:

• after si in unreal/hypothetical conditions, think subjunctive
• in the main clause, think conditional

Tingués comes from tenir = to have.

In this sentence, tingués means had, but specifically in a hypothetical sense:

• Si tingués més temps... = If I had more time...

It does not mean a real statement about actually having time. It presents an imagined situation.

Repassar usually means to review, to go over again, or to revise.

So:

• repassar els apunts = to review the notes

It is similar to estudiar, but not exactly the same:

• estudiar = to study in general
• repassar = to review material you have already studied or written down

So repassaria els apunts suggests going back over existing notes.

Catalan often uses the definite article more than English does.

• els apunts literally = the notes
• in natural English, we often just say notes
• in Catalan, using els here is completely normal

So repassaria els apunts is the natural way to say I would review my/the notes depending on context.

Because Catalan verb endings usually make the subject clear.

• tingués can already suggest the intended subject from context
• repassaria also clearly works as I would review

So jo is often omitted unless you want emphasis or contrast.

For example:

• Si jo tingués més temps... would sound more emphatic, like If I had more time...
• but normally Si tingués més temps... is enough

Usually aquesta tarda means this afternoon.

However, the Catalan word tarda can sometimes cover a time range that overlaps with what English speakers might partly think of as late afternoon / early evening, depending on context.

In this sentence, the idea is simply:

• this afternoon
• before dinner time

So the timing is: later today, during the afternoon, before supper/dinner.

Because sopar here is being used as an infinitive: to have dinner / to eat dinner.

So:

• abans de sopar = before having dinner / before dinner

If you say abans del sopar, that refers more specifically to before the dinner / before the meal/event as a noun.

Compare:

• abans de sopar = before eating dinner
• abans del sopar = before the dinner

In your sentence, the infinitive version is the natural choice.

Yes, somewhat. The given word order is natural and clear:

• Si tingués més temps aquesta tarda, repassaria els apunts abans de sopar.

You could move some time expressions around, for example:

• Si aquesta tarda tingués més temps, repassaria els apunts abans de sopar.
• Si tingués més temps, repassaria els apunts aquesta tarda abans de sopar.

But the original order sounds very natural.

Catalan often places the if-clause first, followed by the result clause, just like English.

When the si-clause comes first, a comma is very commonly written:

• Si tingués més temps aquesta tarda, repassaria els apunts abans de sopar.

This helps separate the condition from the result.

You may sometimes see punctuation used less strictly in informal writing, but with the clause first, the comma is standard and helpful.

You could, but it would sound less natural in English.

A closer literal breakdown is:

• Si = if
• tingués = had / were to have
• més temps = more time
• aquesta tarda = this afternoon
• repassaria = would review
• els apunts = the notes
• abans de sopar = before dinner / before having dinner

But the best natural English translation is still: If I had more time this afternoon, I would review the notes before dinner.

Yes. That is exactly the usual implication.

Because the sentence uses a hypothetical conditional, it suggests that the speaker doesn’t actually have enough time, or at least sees it as unlikely.

So the feeling is:

• If I had more time... → but in reality, I probably don’t

That is why tingués and repassaria are used: they create that unreal or less-real situation.