Postaw proszę kubek przy oknie.

Postaw is the imperative form of the verb postawić, so it means put / place / set as a command or request.

It is the 2nd person singular imperative, used when speaking to one person in an informal way, like you, put the mug...

This is mainly about aspect.

• postawić is perfective
• stawiać is imperfective

In commands, Polish often uses the perfective imperative when you want someone to do one complete action:

• Postaw kubek przy oknie. = Put the mug by the window.

If you said staw kubek, it would sound less natural in this situation, or it could suggest repeated/ongoing action in the right context.

So postaw is the normal choice for a single completed action.

Not exactly.

• postawić means to set / stand / place upright
• położyć means to put / lay down

So:

• Postaw kubek przy oknie suggests placing the mug in a normal standing position.
• Połóż kubek przy oknie would suggest laying it down, which is less natural for a mug unless you really mean on its side.

So postaw is a very natural verb here.

Because kubek is the direct object of the verb postaw, and here it is in the accusative case.

For a masculine inanimate noun like kubek, the accusative singular is usually the same as the nominative singular:

• nominative: kubek
• accusative: kubek

So the form does not change.

You would see a different form with some other noun types, but not here.

Because the preposition przy requires the locative case.

The noun okno in the locative singular becomes oknie:

• nominative: okno
• locative: oknie

So:

• przy oknie = by / near the window

This is a very common pattern in Polish: the preposition determines the case of the noun after it.

Przy usually means by, near, next to, or at depending on context.

In this sentence, przy oknie means something like:

• by the window
• near the window
• next to the window

It does not specifically mean on the window or on the windowsill.

If you wanted on the windowsill, you would usually say na parapecie.

Proszę adds politeness, like please.

So:

• Postaw kubek przy oknie. = Put the mug by the window.
• Postaw proszę kubek przy oknie. = Please put the mug by the window.

In everyday Polish, proszę is very common in requests and makes the command softer.

Yes. Polish word order is fairly flexible, and proszę can appear in different positions.

For example:

• Postaw proszę kubek przy oknie.
• Proszę, postaw kubek przy oknie.
• Postaw kubek przy oknie, proszę.

All of these are natural.

The difference is mostly in tone or emphasis, not in core meaning.

It is polite, but still informal in grammar.

That is because postaw is the imperative used to address one person directly in an informal you form.

If you wanted to be more formal, especially with Pan/Pani, you would more likely say:

• Proszę postawić kubek przy oknie.
• Niech pan postawi kubek przy oknie.
• Niech pani postawi kubek przy oknie.

So the original sentence is polite, but not highly formal.

Yes. Polish allows more word-order flexibility than English.

For example, these are all possible:

• Postaw proszę kubek przy oknie.
• Kubek postaw proszę przy oknie.
• Przy oknie postaw proszę kubek.

However, not all versions sound equally neutral. The original order is natural and straightforward.

Changing the order usually changes emphasis:

• starting with kubek emphasizes the mug
• starting with przy oknie emphasizes the location

So the original sentence is a normal, neutral way to say it.

Roughly:

• przy sounds somewhat like pshih
• oknie sounds roughly like ok-nye

A few important points:

• rz in przy is pronounced like the zh sound in measure, but after p it often blends into something English speakers hear closer to psh
• y in przy is a Polish vowel that does not exist exactly in English
• knie in oknie includes a soft ń-like sound before the final vowel, so it is not a hard English knee, but something closer to k-nye

A rough whole-sentence pronunciation guide could be:

POH-staf PRO-sheh KOO-bek pshee OCK-nyeh

That is only approximate, but it is a useful starting point.

Because Polish does not use articles like English a and the.

So kubek can mean:

• a mug
• the mug

The exact meaning depends on context.

In a real situation, the listener would understand from the context whether you mean any mug or a specific mug.