Vadí ti, když otevřu okno, nebo ti zima nevadí?

Vadí is from the verb vadit, which means to bother, to annoy, to be a problem, or to mind.

In this sentence, Vadí ti, když otevřu okno...? means something like Does it bother you if I open the window? or Do you mind if I open the window?

So vadit is often used where English uses:

• mind
• bother
• be a problem

Examples:

• Nevadí. = It’s okay / No problem.
• Vadí ti hluk? = Does noise bother you?
• Nevadí mi to. = I don’t mind it.

Ti is the unstressed dative form of ty (you, singular informal).

With vadit, the person affected is usually in the dative:

• Vadí ti to. = It bothers you.
• Nevadí mi to. = I don’t mind it.

So in Vadí ti..., ti literally means to you.

This is different from English, where we usually say Do you mind...? Czech often structures it more like:

• It is bothersome to you or
• It bothers you

That is why the dative is used.

That is a very common learner question. Když often means when, but in conversational Czech it can also mean if in sentences like this.

So:

• Vadí ti, když otevřu okno? = Do you mind if I open the window?

Here, když introduces the situation being asked about: if I open the window.

You will often see this pattern:

• Nevadí ti, když přijdu později? = Do you mind if I come later?
• Vadí vám, když si sednu? = Do you mind if I sit down?

So although jestli is the more straightforward word for if in some contexts, když is very natural in this kind of polite question.

Yes, formally it is a present-tense form, but otevřu comes from the perfective verb otevřít, and perfective present forms usually refer to the future.

So:

• otevírám = I am opening / I open (imperfective)
• otevřu = I will open (perfective present with future meaning)

That is why když otevřu okno means if I open the window or more literally if I do open / when I open the window in a future sense.

This is very normal in Czech:

• až přijdu = when I come / when I arrive
• když to udělám = if I do it

Okno is a neuter noun meaning window. Here it is in the accusative singular, because it is the direct object of otevřu.

For this noun, the accusative singular looks the same as the nominative singular:

• nominative: okno
• accusative: okno

So even though the case has changed, the form stays the same.

Yes. Zima is a noun meaning cold.

In ...nebo ti zima nevadí?, it is the thing that does not bother the person:

• zima nevadí = the cold doesn’t bother (you)

So this part is literally something like:

• or does the cold not bother you?

This is different from the very common expression:

• Je ti zima. = You are cold. / You feel cold.

There, zima is also part of a fixed expression, but the structure is different.

Compare:

• Je ti zima? = Are you cold?
• Vadí ti zima? = Does the cold bother you?
• Zima ti nevadí? = Doesn’t the cold bother you?

Czech often does not use a dummy subject like English it.

In English we say:

• Does it bother you if I open the window?

In Czech, you can simply say:

• Vadí ti, když otevřu okno?

The clause když otevřu okno gives the content of what is bothersome, so Czech does not need an extra it.

This is very common. Czech often avoids the kind of grammatical filler words that English requires.

Czech word order is flexible, but there are still patterns.

1. Vadí ti...

This is a very natural way to begin a yes/no question:

• Vadí ti...?
• Líbí se ti...?
• Chceš...?

Also, ti is a clitic, and clitics tend to appear near the beginning of the clause, typically in the second position.

2. ...nebo ti zima nevadí?

Here ti again appears early, and zima is placed before nevadí. This word order is natural and conversational.

You could hear other versions too, depending on emphasis:

• Nebo ti nevadí zima?
• Nebo zima ti nevadí?
  But the given sentence sounds normal and idiomatic.

So the main point is:

• Czech word order is flexible
• ti tends to be early
• the exact order can slightly change emphasis

Yes, absolutely. Nevadí ti, když otevřu okno? is very common.

The difference is mostly one of perspective:

• Vadí ti, když otevřu okno?
  = Does it bother you if I open the window?
• Nevadí ti, když otevřu okno?
  = Do you mind if I open the window? / Is it okay if I open the window?

The version with nevadí often sounds a bit softer or more polite, because it expects or hopes for no problem.

The version with vadí is still perfectly natural, but it can sound a bit more direct.

Because the speaker is contrasting two possibilities:

1. You mind if I open the window
2. The cold does not bother you

So:

• Vadí ti, když otevřu okno, nebo ti zima nevadí?

The second clause suggests:

• maybe you do not mind the cold
• maybe being cold is not a problem for you

This kind of contrast is very normal with nebo (or).

Yes. Ti is singular informal, used with ty.

If you want to be formal or plural, you would use vám:

• Vadí vám, když otevřu okno, nebo vám zima nevadí?

That means:

• Do you mind if I open the window, or does the cold not bother you?

So:

• ti = to you, singular informal
• vám = to you, plural or formal singular

It is understandable and basically natural, but in everyday speech many speakers might choose a slightly simpler or smoother version, depending on the situation.

Very common alternatives would be:

• Vadí ti, když otevřu okno?
• Nevadí ti, když otevřu okno?
• Můžu otevřít okno?
• Není ti zima?
• Nevadí ti otevřené okno?

The full sentence Vadí ti, když otevřu okno, nebo ti zima nevadí? is fine, but it is a bit more specific because it sets up a contrast:

• either opening the window bothers you
• or being cold does not bother you

So yes, it is natural, but it sounds more context-dependent than a simple Můžu otevřít okno?

In this sentence it means cold, not winter.

The word zima can mean both:

• winter
• cold

But context makes the meaning clear.

Here, because the topic is opening a window and whether that bothers someone, zima clearly means cold.

Compare:

• V zimě sněží. = It snows in winter.
• Je mi zima. = I am cold.
• Zima mi nevadí. = The cold doesn’t bother me.

A very useful pattern is:

Vadí + dative + clause / noun

Examples:

• Vadí ti, když přijdu pozdě? = Do you mind if I come late?
• Vadí mu hluk. = Noise bothers him.
• Nevadí nám zima. = The cold doesn’t bother us.

So the key things to remember are:

1. vadit often means to bother / to mind
2. the person affected is in the dative
3. Czech can use když in the sense of if in this type of sentence
4. perfective present like otevřu often refers to the future