Learn Hardcore Czech: Můj kurz češtiny trvá dva měsíce.

kurz češtiny – literally course of Czech (language)
- structure: kurz
  - genitive češtiny (“course of what?”)
- this is the most neutral and common way to say Czech course / Czech class.
český kurz – literally Czech course
- structure: adjective český
  - noun kurz
- this can mean a course that is Czech in some way (e.g. a course held in Czech, or a course about something Czech).
- As “Czech language course”, it’s understandable, but not the most typical phrasing.

If you want to be clear that it’s a language course, kurz češtiny is the natural phrase.

What case is češtiny in, and why?

Češtiny is in the genitive singular of čeština (Czech language).

We use genitive here because kurz behaves like “course of X”:

kurz čeho? – course of what? → češtiny (of Czech)
kurz angličtiny – course of English
kurz španělštiny – course of Spanish

So the pattern is: kurz + [language] in genitive.

Why is it trvá and not just je (is)? Can I say Můj kurz češtiny je dva měsíce?

The verb trvat means to last / to take (time).
For durations, trvat is the normal verb:

Kurz trvá dva měsíce. – The course lasts two months.
Cesta trvá hodinu. – The journey takes an hour.

Můj kurz češtiny je dva měsíce is not natural Czech.
If you want to use je, you normally add na:

Můj kurz češtiny je na dva měsíce. – My Czech course is for two months.

So:

trvá dva měsíce = actually lasts that long
je na dva měsíce = is planned / designed for that long

Why is it dva měsíce and not dvě měsíce?

Czech has two forms of “two”:

dva – with masculine nouns (and masculine animate/inanimate distinction)
dvě – with feminine and neuter nouns

Examples:

dva měsíce – two months (měsíc is masculine)
dva dny – two days (den is masculine)
vs.
dvě hodiny – two hours (hodina is feminine)
dvě auta – two cars (auto is neuter)

Since měsíc (month) is masculine, you must say dva měsíce.

Why is it měsíce and not měsíců?

This is because of how numbers work in Czech.

With 2–4, masculine nouns take a form that (for masculine inanimate) looks like the nominative/accusative plural:

1 měsíc – one month
2–4 měsíce – dva / tři / čtyři měsíce – two/three/four months
5+ měsíců – pět měsíců – five months

So:

dva měsíce – two months
pět měsíců – five months

In our sentence, měsíce is the accusative plural (object expressing duration), and its form is měsíce, not měsíců.

What case is dva měsíce in, and is that always used for durations?

In this sentence, dva měsíce is in the accusative and functions as an object of duration after trvat:

trvá (jak dlouho?) dva měsíce – lasts (how long?) two months

For time expressions with how long?, Czech normally uses the accusative:

Čekám dvě hodiny. – I’m waiting (for) two hours.
Pracoval tam tři roky. – He worked there for three years.
Kurz trvá dva měsíce. – The course lasts two months.

So yes, accusative is the usual case for “for X time” in this type of sentence.

Can I change the word order? For example, say Dva měsíce trvá můj kurz češtiny?

Yes. Czech word order is more flexible than English.

All of these are grammatically correct:

Můj kurz češtiny trvá dva měsíce. – neutral, standard order (subject–verb–object).
Dva měsíce trvá můj kurz češtiny. – emphasizes two months (the duration).
Kurz češtiny můj trvá dva měsíce. – possible but unusual; můj normally goes before kurz.

In everyday speech, the most natural here is:

Můj kurz češtiny trvá dva měsíce.

and, with emphasis on time:

Dva měsíce trvá můj kurz češtiny.

Can I omit můj and just say Kurz češtiny trvá dva měsíce?

Yes.

Kurz češtiny trvá dva měsíce. – The Czech course lasts two months.

Without context, it just means “the (or a) Czech course”, not specifically my course.
In a conversation where it’s already clear that you are talking about your course, you could absolutely drop můj:

– Jak dlouho trvá ten kurz češtiny?
– Trvá dva měsíce.

What is the difference between Kurz češtiny trvá dva měsíce and Kurz češtiny je na dva měsíce?

Both talk about duration, but the nuance is slightly different:

Kurz češtiny trvá dva měsíce.
- focus on actual length – how long it lasts in reality.
Kurz češtiny je na dva měsíce.
- focus on intended/planned duration – it is set up as a two‑month course.

In many contexts they overlap and both are fine, but:

For a factual statement of how long it lasts, trvá is the default.
For advertisement / description of program design, je na often sounds natural.

How would this sentence look in the past and future?

The verb trvat is regular in past and future.

Present:
- Můj kurz češtiny trvá dva měsíce.
  My Czech course lasts two months.
Past:
- Můj kurz češtiny trval dva měsíce.
  My Czech course lasted two months.
  (Past masculine singular: trval because kurz is masculine.)
Future:
- Můj kurz češtiny bude trvat dva měsíce.
  My Czech course will last two months.
You can’t form a simple future trvá → bude trvat; you need být (bude) + infinitive trvat.