Cada sèrie té dues repeticions.

Because cada means each or every, and in Catalan it is followed by a singular noun.

So:

• cada sèrie = each set / every set
• not cada sèries

This works like English each set, not each sets.

Because the subject is grammatically singular: cada sèrie.

Even though the idea refers to all the sets in general, Catalan treats cada + singular noun as singular, so the verb must also be singular:

• Cada sèrie té... = Each set has...

If the subject were plural, the verb would be plural:

• Les sèries tenen... = The sets have...

Because repeticions is a feminine plural noun, and the number two agrees in gender in Catalan:

• dos = masculine
• dues = feminine

Since the singular is la repetició, the plural is dues repeticions.

Compare:

• dos exercicis = two exercises
• dues repeticions = two repetitions

Yes. In an exercise or fitness context, repeticions means repetitions, often equivalent to reps in English.

So this sentence would naturally mean something like:

• Each set has two reps.

Repeticions is the full, standard word. In casual speech, people may also use shorter, more informal forms, but repeticions is perfectly normal and clear.

Yes. In workout language, sèrie is commonly used for set.

So in this context:

• sèrie = set
• repeticions = repetitions / reps

Outside the gym context, sèrie can also mean series, such as a TV series or a sequence of things. Context tells you which meaning is intended.

Because cada normally goes directly before the noun, without an article.

So you say:

• cada sèrie

Not:

• cada la sèrie

This is similar to English:

• each set not
• each the set

Té is the third-person singular form of the verb tenir, which means to have.

So:

• tenir = to have
• té = has

In the sentence:

• Cada sèrie té dues repeticions
• Each set has two repetitions

The accents are part of the correct spelling and also help show pronunciation/stress.

• sèrie has a grave accent on è
• té has an acute accent on é

In té, the accent also distinguishes it from te, which can mean you as an object pronoun in some contexts.

So you should write:

• sèrie
• té

not:

• serie
• te

Yes, that is possible, and it would mean something like In each set there are two repetitions.

But Cada sèrie té dues repeticions is more direct and usually more natural if you simply want to describe what each set contains.

So both are possible, but they are structured differently:

• Cada sèrie té dues repeticions = Each set has two repetitions
• A cada sèrie hi ha dues repeticions = In each set there are two repetitions

The normal, neutral order is:

• Cada sèrie = subject
• té = verb
• dues repeticions = object

So:

• Cada sèrie té dues repeticions

This is the most straightforward word order in Catalan, just like:

• Each set has two repetitions

Other word orders are sometimes possible for emphasis, but this is the standard one learners should use first.