Learn Hardcore Polish: Gdy budzik przestaje dzwonić, sprawdzam pogodę, żeby wiedzieć, czy wziąć parasol. - When the alarm clock stops ringing, I check the weather to know whether to take an umbrella.

In Polish both gdy and kiedy mean “when” in temporal clauses and in many cases you can swap them: • gdy is slightly more literary or neutral in written style;
• kiedy is common in spoken language and can also introduce direct questions (e.g., Kiedy przyjdziesz?).
In our sentence Gdy budzik przestaje dzwonić… you could also say Kiedy budzik przestaje dzwonić… without changing the meaning.

Why is przestaje in the present tense instead of a past tense like przestał?

Here the present tense przestaje expresses a habitual or general situation—every time the alarm stops ringing. Polish uses the present to talk about repeated or regular actions. If you used przestał, it would refer to one specific event in the past (“when the alarm stopped ringing that time”).

What’s the difference between przestaje dzwonić and przestał dzwonić in meaning and aspect?

• przestaje dzwonić (imperfective): describes the process or habit of stopping ringing, often used for repeated or ongoing situations.
• przestał dzwonić (perfective): marks a single, completed action in the past—“it stopped ringing (that one time)”.

Why is sprawdzam (imperfective) used instead of sprawdzę (perfective)?

Imperfective sprawdzam focuses on the action/process of checking (and suits habitual or current actions). Perfective sprawdzę would emphasize the completion of the check (and often shifts it to the future or to a single one-off event). In this context you’re describing what you regularly or immediately do.

What is żeby, and can I use aby or żebym here?

żeby is a conjunction meaning “in order to” or “so that” (introducing a purpose clause).
• aby is a more formal/written synonym of żeby.
• żebym is the same conjunction with the first-person singular (it requires a finite verb form).
You could say aby wiedzieć…, and if you used a finite verb you’d say żebym wiedział, but because the subject is the same you often use żeby + infinitive (żeby wiedzieć) for conciseness.

Why is there an infinitive wiedzieć after żeby instead of a finite form like żebym wiedział?

When the subject of both clauses is the same (here “I”), Polish allows żeby + infinitive to express purpose. It’s shorter and more neutral:
• żeby wiedzieć = “so as to know”
If you want a finite verb form, you must mark the person: żebym wiedział (“so that I would know”), which is more formal.

What role does czy play in czy wziąć parasol?

czy introduces an indirect yes/no question, equivalent to “whether.”
czy wziąć parasol literally means “whether to take an umbrella.” Without czy it would lose the sense of an option/alternative.

Could I say żeby wiedzieć, czy wezmę parasol instead of czy wziąć parasol?

You could, but it changes the nuance:
• czy wziąć parasol uses an infinitive for a general decision “whether to take.”
• czy wezmę parasol uses a finite verb “I will take,” making it sound like you’re wondering about your future action itself. The infinitive version is more common for expressing a choice or plan.

Why is there a comma after dzwonić? Is it mandatory?

Yes. In Polish, an introductory subordinate clause (here Gdy budzik przestaje dzwonić) must be separated by a comma from the main clause (sprawdzam pogodę). It clarifies the sentence structure.

Does this sentence describe a habitual action, and how is that expressed in Polish?

Yes. It describes what you regularly do: every time the alarm stops, you check the weather. Polish uses the simple present (przestaje, sprawdzam) to talk about both current and habitual actions, so context tells you it’s a repeated event.