"Så dere støvet på hyllene?"

Translation: Did you see the dust on the shelves?

[nohoots3pac]

Very odd stress placement on the word "støvet". The voice says it as if støvet was a verb (to dust, dusted).

[Gulpepper]

Yep. The stress is off. It should be rising (in east norwegian)

[NattKullav1]

Å tørke støv, tørket støv should be (to dust, dusted).

[effyleven]

Where does the "all" come from?

[Wiwa4444]

I think Duolingo may have meant "y'all" = "you + all", which is a translation of dere. :)

[helloorca]

What makes this past tense?

[Deliciae]

"Så" is the past tense of "å se", with the present tense being "ser".

[Moongrovenly]

I was surprised to hear the robot voice pronounce the 't' at the end of 'stovet' in the sentence. Clicking just the word alone, we hear a silent final t. And the next word, på, does not begin with a vowel, so neither does that explain the voicing of the t sound. Maybe just a speechbot error?

[skynightstar]

As far as I know, the final 't' in definite neuter nouns is never pronounced. I have never heard of it being pronounced when the next word starts with a vowel. Is that really a thing? But here I think it is definitely a speechbot error, in any case.