Learn Hardcore German: Mein Freund liebt sein rotes Trikot so sehr, dass er es nach dem Spiel sofort wäscht. - My friend loves his red jersey so much that he washes it immediately after the match.

In everyday speech among adults, mein Freund often means my boyfriend.
To make it clear you mean a platonic friend, people sometimes say ein Freund von mir (a friend of mine) or specify: mein Freund, also nur ein guter Freund (my friend, just a good friend).

Without context, mein Freund is ambiguous.

Why is it sein rotes Trikot and not seinen rotes Trikot or seinem roten Trikot?

The phrase sein rotes Trikot is in the accusative case as the direct object of liebt.

The noun Trikot is neuter: das Trikot.
Accusative singular neuter has the same form as nominative: das Trikot.
Possessive sein takes no ending in accusative neuter.
The adjective rot takes the ending -es: rotes.

Pattern (accusative neuter, with possessive):

sein rotes Trikot
mein neues Auto
ihr schönes Haus

Why is the adjective rotes and not rote or roten?

Adjective endings in German depend on case, gender, and article type.

Here we have:

Gender: neuter (das Trikot)
Case: accusative (direct object of liebt)
Determiner: sein (a possessive, counts as a “weak” determiner → mixed declension)

For neuter accusative after a possessive, the ending is -es:

sein rotes Trikot
mein neues Handy
ihr altes Auto

So rotes is the correct mixed-declension ending.

What exactly is a Trikot? Is it just a T-shirt?

A Trikot is a sports jersey, usually the kind worn by a team player, often with a number and name on it.

It’s not just any T‑shirt:

das T‑Shirt – general T‑shirt of any kind
das Trikot – jersey for sports (football, basketball, cycling, etc.)

In this sentence, it suggests a team shirt that he wears for a game.

Why is it sein and not ihr, seinen, etc.? How does sein agree?

Sein refers to er (er liebt sein rotes Trikot), so it means his.

Two things matter:

Owner:
- er → sein (his)
- sie (she) → ihr (her)
- es → sein (its)
The thing owned controls the ending:
- das Trikot is neuter, accusative → base form sein
  - adjective rotes.

So:

Er liebt sein rotes Trikot. – He loves his red jersey.
Sie liebt ihr rotes Trikot. – She loves her red jersey.

Why is there a comma before dass, and why does the verb go to the end in dass er es nach dem Spiel sofort wäscht?

Dass introduces a subordinate clause (a dependent clause). In German:

Subordinate clauses are separated by a comma.
The finite verb of the subordinate clause goes to the end.

Main clause:

Mein Freund liebt sein rotes Trikot so sehr, …

Subordinate clause:

… dass er es nach dem Spiel sofort wäscht.
Subject = er, object = es, verb = wäscht at the end.

So both the comma and verb-final order are standard rules for dass-clauses.

What does the structure so sehr, dass … mean exactly?

The pattern so …, dass … expresses a degree that leads to a result (so X that Y).

Here:

so sehr = so much / so strongly
dass er es nach dem Spiel sofort wäscht = that he washes it immediately after the game

Together:

Mein Freund liebt sein rotes Trikot so sehr, dass er es nach dem Spiel sofort wäscht.
→ My friend loves his red jersey so much that he washes it immediately after the game.

Why is it wäscht with an umlaut, and how is waschen conjugated?

Waschen is a strong verb with a stem vowel change (a → ä) in the du and er/sie/es forms in the present tense.

Present tense conjugation:

ich wasche
du wäschst
er/sie/es wäscht
wir waschen
ihr wascht
sie/Sie waschen

So for er you must say er wäscht, not er wascht.

Why is it wäscht es and not wäscht sich? When is waschen reflexive?

Waschen can be:

transitive (washing something):
- Er wäscht das Trikot. – He washes the jersey.
- Er wäscht es. – He washes it.
reflexive (washing oneself):
- Er wäscht sich. – He washes himself.
- Er wäscht sich die Hände. – He washes his hands.

In this sentence, he is washing the jersey, not himself, so es is the correct object pronoun: er wäscht es.

Why is the pronoun es used for Trikot?

The pronoun for a noun in German must match the noun’s grammatical gender and number, not the natural gender.

das Trikot → neuter singular → pronoun es

Examples:

Wo ist das Trikot? Ich kann es nicht finden.
Where is the jersey? I can’t find it.

So in dass er es nach dem Spiel sofort wäscht, es clearly refers back to sein rotes Trikot.

Why does nach dem Spiel take the dative case?

The preposition nach (in the sense of after time-wise) always takes the dative case.

nach + Dativ

Here:

das Spiel → dative singular: dem Spiel
So: nach dem Spiel = after the game

Other examples:

nach der Arbeit – after work
nach dem Unterricht – after class

Is the word order nach dem Spiel sofort wäscht fixed, or could it be sofort nach dem Spiel wäscht?

You can move adverbials around quite flexibly in German. All of these are possible:

… dass er es nach dem Spiel sofort wäscht.
… dass er es sofort nach dem Spiel wäscht.
… dass er es nach dem Spiel gleich wäscht.

The finite verb (wäscht) must stay at the end of the subordinate clause, but the order of time adverbs like nach dem Spiel and sofort can vary slightly for emphasis or style.
Sofort nach dem Spiel is slightly more natural than nach dem Spiel sofort, but both are acceptable.

Why is it liebt and not mag? Is there a difference between lieben and mögen here?

Both lieben and mögen can express liking, but:

lieben = to love, stronger emotion, often used for people, but also for things you are very attached to.
mögen = to like, weaker, more neutral.

So:

Mein Freund liebt sein rotes Trikot… – suggests he is very attached, almost emotionally.
Mein Freund mag sein rotes Trikot… – simply says he likes it.

Using liebt fits well with so sehr, dass … because it emphasizes a strong feeling that leads to that result.

Could we use weil instead of dass here, e.g. …, weil er es nach dem Spiel sofort wäscht? Would that mean the same?

You can say:

Mein Freund liebt sein rotes Trikot, weil er es nach dem Spiel sofort wäscht.

But the meaning changes:

so sehr, dass … → degree + result (He loves it so much that he does this.)
weil … → cause/reason (He loves it because he does this.)

In the original, loving the jersey is the cause and washing it immediately is the result.
With weil, you’d be saying he loves it because he washes it, which is a bit odd logically. That’s why so sehr, dass … is more natural here.