Learn Hardcore Swedish: Kaffet är starkt idag, vilket gör mig nervös. - The coffee is strong today, which makes me nervous.

Swedish usually marks definiteness with a suffix. Kaffe is the base (indefinite) form of a neuter noun meaning coffee in general. Kaffet adds the definite ending -et and means the coffee (the specific coffee we’re talking about, e.g., today’s brew).

Why is the adjective stark written as starkt?

In predicative position (after är), adjectives agree with the subject’s gender and number. Kaffe is a neuter (ett) word, so the adjective takes the neuter -t: starkt. Compare:

Bilen är stark (en-word, common gender).
Huset är starkt (ett-word, neuter).
Bilarna/Husen är starka (plural).

Can I say Kaffet är stark idag?

Not in standard Swedish. With a neuter subject (kaffet), you need the t-form: starkt.

Where does idag go? Can I move it?

Yes. Neutral order is Kaffet är starkt idag. You can also front it for emphasis: Idag är kaffet starkt. Putting it mid-clause (Kaffet är idag starkt) is grammatical but sounds more formal or contrastive.

Is there a difference between idag and i dag?

Both are correct and mean the same. I dag is the traditional spacing; idag is very common in modern writing. Style guides differ, but either is fine for learners.

What is vilket doing here? Does it refer to kaffet?

Here vilket is a relative pronoun that refers to the entire preceding clause (Kaffet är starkt idag)—the fact that the coffee is strong—rather than to the noun kaffet itself. It’s neuter by convention when it refers to a whole statement.

Could I use som instead of vilket?

Not with the same meaning and structure. Som normally refers to a specific noun. If you try Kaffet är starkt idag, som gör mig nervös, it’s ungrammatical. To use som, you’d restructure: Kaffet, som är starkt idag, gör mig nervös (the coffee, which is strong today, makes me nervous). With vilket, you’re saying the fact that it’s strong makes you nervous.

Do I need the comma before vilket?

Yes. This is a non-restrictive, clause-level relative; Swedish uses a comma before vilket in this use. Without the comma it looks odd and is against standard punctuation practice.

Can I just say Det gör mig nervös instead of vilket gör mig nervös?

Yes. Det gör mig nervös is common and a bit more conversational. ..., vilket gör mig nervös is typical in writing and slightly more formal.

Is gör mig nervös the normal way to say “makes me nervous”?

Yes. The pattern is göra + någon + adjektiv: gör mig nervös, gör honom glad, etc. Alternatives:

Jag blir nervös av det (I get nervous from that).
Det får mig att bli nervös (makes me become nervous; more verbose).

Why mig and not jag?

Mig is the object form of jag. After gör (makes), you need the object: gör mig. Using jag here would be ungrammatical.

How do attributive forms look? For example, “strong coffee.”

Before a noun, the adjective also agrees:

Indefinite neuter: starkt kaffe (some strong coffee).
Definite neuter: det starka kaffet (the strong coffee).

Any pronunciation tips for tricky words like gör, nervös, starkt, vilket, kaffet?

ö (in gör, nervös) is like French eu in “peur” or German ö in “schön.”
gör starts with a soft g, often sounding like an English y: roughly “yur” with rounded lips.
starkt has a consonant cluster at the end; pronounce the k and t: “stark-t.”
vilket has a hard k [k], not a sh-sound.
kaffet has a short a (because of the double f) and stress on the first syllable: KAFF-et.

Does stark mean “caffeinated,” “strongly brewed,” or “spicy”?

In the context of coffee, stark means strong in taste/strength (heavily brewed, high in potency). It doesn’t mean spicy. For caffeine content specifically, Swedes still say starkt kaffe or clarify with context.