Ja wstaję o siódmej.

Usually, ja is not necessary here. Polish often leaves out subject pronouns because the verb ending already shows who is doing the action.

• wstaję already means I get up / I am getting up
• So Wstaję o siódmej is a very natural sentence

You include ja for emphasis, contrast, or clarity, for example:

• Ja wstaję o siódmej, ale on o ósmej.
  I get up at seven, but he gets up at eight.

So in this sentence, ja adds a bit of emphasis, but it is not required.

Wstaję is the 1st person singular present tense form of wstawać, which means to get up, to stand up, or sometimes to rise, depending on context.

In this sentence:

• wstaję o siódmej = I get up at seven

Because it is present tense in Polish, it can describe:

• a habit: I get up at seven
• sometimes a current action, depending on context: I’m getting up

But with o siódmej, it most naturally means a habitual action.

After the preposition o when talking about clock time, Polish uses the locative case, not the plain number.

So:

• o siódmej = at seven
• not o siedem

This is because Polish treats the hour like an implied phrase such as at the seventh hour, so it uses an ordinal number form.

Compare:

• o pierwszej = at one
• o drugiej = at two
• o siódmej = at seven
• o dziesiątej = at ten

So English uses a cardinal number (seven), but Polish uses an ordinal-style form in this structure.

Siódmej is the locative singular feminine form of siódma (seventh).

The full idea is historically like:

• o siódmej godzinie = at the seventh hour

The noun godzina (hour) is feminine, so the number agrees with it:

• base form: siódma
• after o: siódmej

Even when godzinie is omitted, the feminine locative form stays:

• o siódmej

So this is really about case and agreement.

In normal usage, it means:

• I get up at seven

That is, a habit or regular schedule.

Polish present tense can sometimes overlap with English simple present and present continuous, but here the time phrase o siódmej strongly suggests a routine or scheduled action, not something happening right now.

So a learner should usually understand this as:

• I get up at seven
• or I wake/get up at seven o’clock, depending on context

This is a question of aspect, which is very important in Polish.

• wstawać = imperfective
• wstać = perfective

In practice:

• wstawać focuses on the process, repetition, or habit
• wstać focuses on the completed action

Examples:

• Codziennie wstaję o siódmej.
  I get up at seven every day.
  Habit → imperfective

• Jutro wstanę o siódmej.
  Tomorrow I will get up at seven.
  Single completed future action → perfective

So in your sentence, wstaję is used because it describes a regular action.

Yes. Polish word order is fairly flexible, though not completely free. Because verb endings show the subject, you can move parts around for emphasis.

Common versions include:

• Ja wstaję o siódmej.
• Wstaję o siódmej.
• O siódmej wstaję.

They all basically mean the same thing, but the focus changes slightly:

• Ja wstaję o siódmej. → emphasis on I
• Wstaję o siódmej. → neutral
• O siódmej wstaję. → emphasis on the time

For a beginner, Wstaję o siódmej is probably the most neutral everyday version.

A rough guide:

• wstaję ≈ fsta-yeh (very roughly)
• siódmej ≈ SHOOD-may or SYOOD-may, depending on how exact you want to be

A few key points:

• w in Polish sounds like English v/f-like depending on position; in wstaję, it becomes devoiced, so it sounds closer to f
• j sounds like English y in yes
• ę is a nasal vowel, but at the end of a word it is often pronounced more simply in everyday speech
• si before a vowel gives a soft ś-like sound

You do not need perfect pronunciation immediately, but it helps to know that Polish spelling is usually quite consistent.

You keep o and change the hour form:

• o pierwszej = at one
• o drugiej = at two
• o trzeciej = at three
• o czwartej = at four
• o piątej = at five
• o szóstej = at six
• o siódmej = at seven
• o ósmej = at eight

So you can build similar sentences:

• Wstaję o szóstej. = I get up at six.
• Wstaję o ósmej. = I get up at eight.

This pattern is worth memorizing because it is very common in everyday Polish.