Learn Hardcore Czech: Prosím vás, otevřete dveře, někdo čeká venku. - Please, open the door, someone is waiting outside.

say just Prosím. = “Please.” / “Here you go.” / “Pardon?” (very flexible)
or Prosím vás to sound more like “Excuse me, could you…?” and to get someone’s attention politely.

The vás emphasizes you are speaking politely/formally to you (vy), not informally to ty.

Why is the verb otevřete and not something like otevři?

otevřete is the imperative (command/request form) for 2nd person plural / formal “you” (vy).

infinitive: otevřít – to open
informal singular imperative (to 1 friend): Otevři!
formal or plural imperative (to strangers, or to more people): Otevřete!

In your sentence, you are speaking politely to someone you don’t know (or to several people), so Czech uses the vy-form:

Prosím vás, otevřete dveře…
≈ “Please, (you – formal), open the door…”

If you spoke to a close friend or child, you would say:

Prosím tě, otevři dveře, někdo čeká venku.

Why is dveře plural in Czech, when “door” is singular in English?

In Czech, dveře is always grammatically plural, even if it’s just one physical door.

dveře = door / doors (plural-only noun)

Examples:

Otevři dveře. – “Open the door.”
Zavři dveře. – “Close the door.”
Tyhle dveře jsou nové. – “This door is new.” (literally “These doors are new.”)

So even when English uses singular “door”, Czech still uses the plural form dveře with plural agreement:

ty dveře jsou (not je)

What case is dveře in here, and how can I tell?

In Otevřete dveře, dveře is in the accusative case (direct object of the verb).

You’re doing something to the door: open the door.
For many feminine nouns ending in -e (like dveře), the nominative plural and accusative plural look the same: dveře.

So here:

verb (imperative): otevřete
direct object (accusative): dveře

Is Prosím vás, otevřete dveře as soft/polite as English “Could you open the door, please?” or is it stronger, like “Open the door”?

Functionally, Prosím vás, otevřete dveře sits somewhere between:

“Open the door.” (imperative) and
“Could you open the door, please?” (polite request)

Because:

otevřete is a direct imperative, which on its own can sound quite strong:
Otevřete dveře. = “Open the door.”
Adding Prosím vás at the beginning makes it sound polite and respectful, similar to “Excuse me, could you…” in English.

Context and tone matter a lot. Said kindly, it’s a perfectly polite request to a stranger (e.g. in an office or apartment building).

Can I say Otevřete dveře, prosím vás or Otevřete dveře, prosím instead? Is the word order important?

Yes, you can change the word order:

Prosím vás, otevřete dveře…
Otevřete dveře, prosím vás…
Otevřete dveře, prosím…

All are natural. The differences are subtle:

Prosím vás at the beginning feels like “Excuse me…” to get attention, then the request.
…, prosím vás or …, prosím at the end feels more like adding “please” after the actual request.

All are polite. Word order here is flexible and doesn’t change the basic meaning.

What is the difference between Prosím vás and Prosím tě?

Both mean roughly “please” / “excuse me”, but they differ in formality:

Prosím vás
- formal singular “you” (to a stranger, older person, in a shop, at work)
- or plural “you” (to several people)
Prosím tě
- informal singular “you” (to a friend, family member, child)

Examples:

To a shop assistant: Prosím vás, kde je záchod?
To your friend: Prosím tě, otevři okno.

Why is it někdo čeká venku and not something like někdo je venku čekající?

Czech usually prefers a single finite verb instead of English-style “be + -ing” or participle constructions.

čeká is a full verb: is waiting
někdo čeká venku = literally “someone waits outside”, which corresponds to English “someone is waiting outside”.

The construction někdo je venku čekající is very unnatural in everyday Czech. You only use participles like čekající in special, often formal written contexts (e.g. čekající pacienti = waiting patients).

What is the difference between venku and ven?

Both are related to “outside”, but:

venku = “outside” as a location (where something/someone is, static)
- někdo čeká venku – someone is waiting outside
- Jsem venku. – I’m outside.
ven = “out” as a direction (movement to the outside)
- Jdu ven. – I’m going out.
- Vyhoď to ven. – Throw it out.

In your sentence, the person is already there, so Czech uses venku (location).

Could I say Venku někdo čeká instead of někdo čeká venku? Does the word order change the meaning?

Yes, you can say both:

Někdo čeká venku.
Venku někdo čeká.

The basic meaning is the same: Someone is waiting outside.

The nuance:

Někdo čeká venku – more neutral, focusing first on someone.
Venku někdo čeká – slightly emphasizes outside (e.g. answering “Where is he?”).

In everyday conversation, both are fine; the difference is small.

Why is there a comma between Prosím vás and otevřete dveře?

Prosím vás here functions like a separate introductory phrase (address + polite softener), so Czech writing usually separates it with a comma:

Prosím vás, otevřete dveře…

It’s similar to English:

“Excuse me, could you open the door?”
“Please, open the door.”

In speech, you naturally pause a bit after Prosím vás, and the comma reflects that.

If I want to say this informally to a friend, how do I change the sentence?

Use the ty-form (informal singular):

Prosím tě, otevři dveře, někdo čeká venku.

Changes:

vás → tě (informal “you”, accusative singular)
otevřete → otevři (imperative for ty)

Everything else stays the same.

Why is the subject “you” not written in Otevřete dveře?

In Czech, personal pronouns like já, ty, on, vy are often omitted because the verb ending already shows the person and number.

otevřete clearly tells us it’s vy (you – plural/formal), so you don’t need to say Vy otevřete dveře.

You can say Vy otevřete dveře to add emphasis, for example:

Vy otevřete dveře, ne já. – You open the door, not me.

But in neutral speech, just Otevřete dveře is normal and expected.