Lagkamraterna samarbetar för att blockera motspelaren.

Because Swedish makes compounds very freely, and they are normally written as one word.

• lag = team
• kamrat = friend / mate / companion
• lagkamrat = teammate
• lagkamrater = teammates
• lagkamraterna = the teammates

A good rule: if English uses several words for one idea, Swedish often packs them into a single compound.

-na is the definite plural ending, so it means the.

So:

• lagkamrater = teammates
• lagkamraterna = the teammates

Swedish often puts the definite article at the end of the noun instead of using a separate word like English the.

Because Swedish usually attaches the to the noun itself.

In this sentence:

• lagkamraterna = the teammates
• motspelaren = the opposing player / the opponent

This is very common in Swedish:

• bok = book
• boken = the book
• böcker = books
• böckerna = the books

So the definiteness is built into the noun form.

samarbetar is the present tense of samarbeta = to cooperate / to work together.

So:

• samarbeta = to cooperate
• samarbetar = cooperate / are cooperating

In Swedish, the present tense form is the same for all persons:

• jag samarbetar = I cooperate
• du samarbetar = you cooperate
• de samarbetar = they cooperate

Unlike English, Swedish verbs do not change depending on the subject.

för att introduces a purpose, meaning in order to or simply to.

So:

• Lagkamraterna samarbetar för att blockera motspelaren.
• The teammates work together in order to block the opponent.

Here:

• för att = in order to / to
• blockera = to block

This is a very common Swedish pattern for expressing why someone does something.

Because after för att, Swedish normally uses the infinitive.

So:

• för att blockera = to block / in order to block

This is similar to English:

• They cooperate to block the opponent.

The infinitive form is the dictionary form of the verb:

• blockera = to block

motspelaren comes from:

• mot- = against / opposing
• spelare = player
• motspelare = opposing player / opponent
• motspelaren = the opposing player / the opponent

So it is a compound noun, just like lagkamraterna.

Depending on context, motspelare can often be translated naturally as opponent.

It suggests the sentence is talking about one specific opposing player.

Compare:

• motspelaren = the opponent / the opposing player
• en motspelare = an opponent
• motspelare = opponents / opponent players (indefinite plural or general plural, depending on context)

So the Swedish sentence is not just talking about opponents in general, but about the particular player they are trying to block.

The structure is:

• Lagkamraterna = subject
• samarbetar = verb
• för att blockera motspelaren = purpose phrase

So the sentence follows normal Swedish main-clause order:

Subject + verb + rest

Also, Swedish is a V2 language, which means the finite verb usually comes in the second position in a main clause. Here that happens naturally because the subject comes first:

• Lagkamraterna samarbetar ...

If another element came first, the verb would still stay second:

• I försvaret samarbetar lagkamraterna för att blockera motspelaren.
• In defense, the teammates cooperate to block the opponent.

Yes. The Swedish present tense samarbetar can often correspond to either:

• cooperate
• are cooperating

Which English version sounds best depends on context.

So all of these can be reasonable translations:

• The teammates cooperate to block the opponent.
• The teammates are cooperating to block the opponent.
• The teammates work together to block the opponent.

Swedish does not always force the same simple-vs-progressive distinction that English does.

Often yes, but it can also be used without naming the partner if it is obvious from context.

In this sentence, the subject itself is plural:

• Lagkamraterna samarbetar = The teammates cooperate / work together

Since the teammates are already the group doing the action together, Swedish does not need to say with each other explicitly.

If needed, Swedish could make that more explicit in other sentences, for example with med:

• De samarbetar med varandra.
• They cooperate with each other.

Here, though, that would be unnecessary because the idea is already clear.