Breakdown of Она ведь всегда вытирает пыль с полки!
она
she / it (for a feminine noun)
всегда
always
полка
shelf
ведь
after all / you know
Questions & Answers about Она ведь всегда вытирает пыль с полки!
Why do we use с for 'off' here instead of из?
The choice of preposition for 'from' or 'off of' depends on where the object was originally. Since dust sits on a surface (using на), removing it requires the matching opposite preposition с (followed by the genitive case). If the dust were originally inside something (using в), you would use из.
Where does 'you know' come from in the translation? I don't see the word for 'know'.
It comes from the particle ведь. Ведь doesn't literally mean 'to know', but it's used to point out a fact that the speaker believes the listener already knows or should agree with. In English, we usually express this flavor by saying 'you know...', 'after all...', or 'but...'.
Since с takes the genitive case, why doesn't полка (shelf) change to полкы?
This is due to the 7-letter spelling rule. While feminine nouns ending in -а usually change to -ы in the genitive, you can never write the letter ы after к (or after г, х, ш, ж, ч, щ). Therefore, полка becomes полки.
Is пыль (dust) in the nominative or accusative case here?
It is in the accusative case because it is the direct object receiving the action (she wipes the dust). However, because пыль is a feminine noun ending in a soft sign (-ь), its accusative form looks exactly the same as its nominative form.