Learn Hardcore Polish: Z powodu choroby ona jeszcze pracuje z domu. - Because of illness she is still working from home.

You can drop it. Polish usually omits subject pronouns because the verb ending shows person and number. Use ona to emphasize contrast or to make the gender explicit.

Natural: Z powodu choroby jeszcze pracuje z domu.
With emphasis/contrast: Z powodu choroby ona jeszcze pracuje z domu (e.g., “she still does, others don’t”).

Why is it choroby and not choroba?

Because z powodu (“because of”) takes the genitive case. Choroba (illness) is nominative; its genitive singular is choroby. So: z powodu choroby = “because of (an) illness.”

What case is domu in z domu, and why?

It’s genitive singular. The preposition z meaning “from/out of” takes the genitive: z domu (“from home/house”). Contrast: z meaning “with” takes the instrumental: z kolegą (“with a colleague”).

Why z domu (“from home”) and not w domu (“at home”)? Are both okay?

Both are used, but they nuance differently:

pracować z domu = work from home (the remote-work idea).
pracować w domu = work at home (physical location), which can be understood as remote work but can also mean simply doing work in one’s house. You can also say pracować zdalnie (“work remotely”) without mentioning home.

What’s the difference between z powodu, przez, bo, and ponieważ for giving reasons?

z powodu + Gen. = neutral/standard “because of, due to” a noun: z powodu choroby.
przez + Acc. = “because of” (often more informal; can suggest an unwanted cause or even blame): przez chorobę.
bo = “because” + clause: bo jest chora (“because she is ill”).
ponieważ = more formal “because” + clause: ponieważ jest chora.

Where should I place jeszcze?

Default is before the verb or the phrase it modifies:

Very natural: Ona jeszcze pracuje z domu.
With the reason fronted: Z powodu choroby jeszcze pracuje z domu. Putting jeszcze after the verb (e.g., pracuje jeszcze z domu) is possible but less neutral and tends to sound marked; beginners are safest keeping it before the verb.

What’s the nuance between jeszcze, nadal, wciąż, and ciągle?

All can mean “still,” but:

jeszcze = “still/yet” (very common, neutral).
nadal = “still/continuing” (neutral, a bit bookish/formal).
wciąż = “still/continually” (can suggest ongoing continuity).
ciągle = “constantly/continually,” often with an annoyed tone (“all the time”). Negative counterpart: już nie = “no longer.” Example: Ona już nie pracuje z domu.

Does jeszcze also mean “yet” (as in “not yet” or in questions)?

Yes.

Question: Czy ona jeszcze pracuje z domu? (“Does she still work from home?”)
Negative: Ona jeszcze nie pracuje w biurze. (“She isn’t working in the office yet.”)
Affirmative contrast: Ona już pracuje w biurze. (“She already works in the office.”)

Should there be a comma after Z powodu choroby?

No. A short initial prepositional phrase like Z powodu choroby does not take a comma. So: Z powodu choroby ona jeszcze pracuje z domu.

Is pracuje “works” or “is working”?

Both. Polish present tense covers simple and progressive meanings. Context decides:

Habit/current policy: “She still works from home.”
Ongoing situation: “She is still working from home.”

How do you pronounce tricky parts like z powodu, choroby, z domu?

z powodu: the initial z devoices before p, so it sounds like “s-powodu”; ó sounds like English “oo”; ł like English “w”.
choroby: ch is a guttural “kh” (as in Scottish “loch”); stress on the second-to-last syllable: cho-RO-by.
z domu: the z stays voiced before d (sounds like “zdomu”); stress: DO-mu. Polish stresses the penultimate syllable in each word.

Why not ze domu or ze powodu? When do I use ze instead of z?

Use ze before certain consonant clusters or words starting with s-/z- sounds for ease of pronunciation: ze szkoły (“from school”), ze mną (“with me”), ze względu na (“due to”). But here it’s z domu and z powodu.

Is z powodu choroby the same as z choroby or na chorobę?

No.

For “because of illness,” say z powodu choroby (or ze względu na chorobę).
na + Acc. is used with many health verbs: chorować na grypę (“be ill with flu”), umrzeć na chorobę (“die of a disease”).
z choroby is generally not used to express “because of illness.”

Can I move the reason to the end: Ona jeszcze pracuje z domu z powodu choroby?

Grammatically yes, and it’s understandable, but Polish often prefers the cause up front for clarity and flow: Z powodu choroby ona jeszcze pracuje z domu.

Is pracować z domu natural Polish, or a calque from English?

It’s common and accepted in contemporary Polish, especially since remote work became widespread. Alternatives:

pracować zdalnie (work remotely)
pracować w domu (work at home), which may be more literal/locative.