Learn Hardcore German: Dieses Fach ist interessant, aber schwer.

school subject:
- Mein Lieblingsfach ist Englisch. – My favourite subject is English.
field / area (of expertise):
- Er ist Experte in seinem Fach. – He is an expert in his field.
compartment / shelf section (e.g. in a cupboard, drawer organiser, or letter box):
- Die Schlüssel liegen im oberen Fach. – The keys are in the top compartment.

So here, from context, it clearly means school subject.

Why is it Dieses Fach and not Dieser Fach or Diese Fach?

Because Fach is neuter in German: das Fach.

The demonstrative dies- (this) changes depending on gender, case, and number. In the nominative singular:

dieser – masculine (like dieser Tisch)
diese – feminine (like diese Lampe)
dieses – neuter (like dieses Fach)

Since Fach is neuter and is the subject of the sentence (nominative case), you must say dieses Fach.

What gender is Fach, and what is its plural?

Gender: neuter → das Fach
Plural: die Fächer

Notice the vowel change a → ä and the added -er:

Singular: das Fach
Plural: die Fächer

Example in plural:

Diese Fächer sind interessant, aber schwer. – These subjects are interesting but hard.

Why don’t we say das dieses Fach? Why is there no article like das?

Dieses already functions like a determiner (like this in English), so you do not add a normal article in front of it.

You have two basic options:

With normal article:
- Das Fach ist interessant. – The subject is interesting.
With demonstrative:
- Dieses Fach ist interessant. – This subject is interesting.

You do not combine them:

✗ das dieses Fach – wrong

So dieses replaces das in this sentence.

What case is dieses Fach in, and why?

Dieses Fach is in the nominative case because it is the subject of the sentence.

Basic rule: the subject of a normal sentence is nominative. In Dieses Fach ist interessant, aber schwer:

Dieses Fach → subject → nominative
ist → verb
interessant, aber schwer → predicate (what is said about the subject)

If you changed the sentence to use Fach as an object, you would see a different form:

Ich finde dieses Fach interessant. – I find this subject interesting.
- Here dieses Fach is accusative neuter → same form as nominative.

Why do interessant and schwer have no endings here (like -es or -e)?

Because here they are used as predicate adjectives, not before a noun.

Two main patterns:

Before a noun → adjective endings needed
- ein interessantes Fach – an interesting subject
- ein schweres Fach – a hard/difficult subject
After a form of sein (or similar verbs like werden, bleiben) → no ending
- Dieses Fach ist interessant.
- Dieses Fach ist schwer.

So:

Dieses Fach ist interessant. ✅ (no ending)
Dieses interessante Fach ✅ (ending: -e)

The adjectives only get endings when they directly modify a noun.

Is the word order fixed? Why is ist in second position?

German main clauses usually follow the verb-second rule (V2): the finite verb (here ist) must be in second position in the sentence.

In Dieses Fach ist interessant, aber schwer:

Dieses Fach → first position (the entire subject phrase counts as “first”)
ist → second position (finite verb)
interessant, aber schwer → the rest of the sentence (predicate)

You can move elements around, but the finite verb stays second:

Dieses Fach ist interessant.
Heute ist dieses Fach interessant.
Interessant ist dieses Fach nicht.

In all cases: the finite verb (ist) is in position 2.

Why is there a comma before aber? Could we leave it out?

In German, you normally must use a comma before the coordinating conjunction aber.

Aber is a coordinating conjunction like und, oder, denn. Unlike English – where the comma before but is often optional and stylistic – German spelling rules require it in many cases:

Dieses Fach ist interessant, aber schwer. ✅
Dieses Fach ist interessant aber schwer. ❌ (incorrect in standard writing)

So: keep the comma.

What exactly does aber do here?

Aber is a coordinating conjunction meaning but. It introduces a contrast:

Positive aspect: interessant
Negative or challenging aspect: schwer

So the structure is:

X ist interessant, aber schwer. – X is interesting but hard.

Word order after aber remains that of a main clause (verb second). If there were another verb, it would still be in second position after aber:

Dieses Fach ist interessant, aber es ist schwer.

Can I say Dieses Fach ist aber schwer? Does that mean the same thing?

Dieses Fach ist aber schwer is also correct, but the meaning and tone are a bit different.

Dieses Fach ist interessant, aber schwer.
- Neutral, balanced: It is interesting, but (on the other hand) it is hard.
Dieses Fach ist aber schwer.
- Sounds more like an emotional comment, similar to: Wow, this subject really is hard.
- aber here functions more like a flavouring particle than a strict but.

So both are correct, but the original sentence uses aber as a clear contrast between two adjectives.

What is the difference between schwer and schwierig? Could I use schwierig here?

Both can often be translated as difficult, but there are nuances.

schwer
- literally: heavy
- also: difficult, hard (mentally or physically)
- a bit more informal / everyday in many contexts
schwierig
- mainly: difficult, complicated, tricky
- often sounds a bit more formal or precise

In this sentence, both are fine:

Dieses Fach ist interessant, aber schwer.
Dieses Fach ist interessant, aber schwierig.

Often they’re interchangeable, especially for school subjects. Sometimes schwer emphasizes the effort / burden, while schwierig emphasizes complexity.

How do you pronounce Fach and especially the ch?

Fach is pronounced roughly like fahkh in English transcription.

Details:

F → like English f
a → like u in cut or a in father, but short
ch after a back vowel (a, o, u, au) sounds like a voiceless velar fricative, similar to the ch in Scottish loch or German Bach
Final -ch is never like English ch in cheese

IPA: [fax] (with x representing that harsh ch sound).

You can compare:

Fach → back ch ()
ich → front ch ([ç])

How would the sentence change in the plural: These subjects are interesting but hard?

You need:

plural of dieses → diese (same for all genders in nominative plural)
plural of das Fach → die Fächer
plural verb sind

So:

Diese Fächer sind interessant, aber schwer. – These subjects are interesting but hard.

Structure stays the same:

Diese Fächer (subject, nominative plural)
sind (verb, 3rd person plural)
interessant, aber schwer (predicate adjectives).

Could I say Dieses Fach ist interessant, aber es ist schwer? Why is the shorter version preferred?

Yes, Dieses Fach ist interessant, aber es ist schwer is grammatically correct.

However, native speakers usually avoid repeating the subject and verb unnecessarily when both clauses share them. They prefer the more concise:

Dieses Fach ist interessant, aber schwer.

The shorter sentence sounds more natural and smooth in German, just like in English:

This subject is interesting but hard. (not usually: This subject is interesting but it is hard.)

You only repeat es ist if you want to add extra emphasis or if the two parts are longer and need to be clearly separated.

What is the difference between dieses Fach and just das Fach?

Both are correct, but they differ in specificity / pointing.

das Fach
- the subject in a general or already-known context
- less “pointing”
dieses Fach
- this subject (the one right here / the one we are currently talking about, maybe just mentioned or visible on a timetable or list)
- more emphatic and specific, like you’re pointing at it

Examples:

Das Fach ist interessant, aber schwer. – The subject is interesting but hard.
Dieses Fach ist interessant, aber schwer. – This particular subject is interesting but hard.

The original sentence uses dieses, so it feels like someone is referring to a specific subject (e.g. Math, Chemistry) in a given context.