When do you use 'det' and and when do you use 'den'?

[Vathn]

Have I missed something?

[landsend]

Did you already do the lessons "Definites" and "Adj. 1"?

en words - den, en bil - den gula bilen

ett words - det, ett hus - det gula huset

Plural (en and ett) - de, klockor - de gula klockorna

[Vathn]

No, I didn't take those lessons yet, I am at the possession lessons.
It just really annoys me when Duo doesn't explain these kind of things when they are already relevant, so I really wanted to know when to use when so I actually know what I'm doing instead of memorising sentences, because I don't think that that helps learning at all.

Thank you.

[lizlensky]

Although when you use "den" or "det", the noun also changes: den gula bilEN, det gula husET, de gula klockorNA

en-words get -en while ett-words get -et and plurals get -na

[landsend]

Thanks for the hint, I corrected that. Generally I am aware of it, I wrote this in the midst of a Danish session where this is different.