"Weź" is a singular action, usually 'right now', 'bierz' is general, may be regular. But in some contexts it may work perfectly instead of 'weź', like in a shop: "Mamo, mogę cukierka?" "Bierz co chcesz/Weź co chcesz".
In the word brick tasks of the mobile app I often get bricks with grammatical categories, such as nom(inative), sg (singular), or imper(ative). Wherever I put these they are always marked as wrong. Anybody know how to use them properly?
I have never, ever tapped on one of those. I think that they are meant to throw you off
Well, they were never meant to be there in the first place, tbh – it's just that course was build with these in hints and we only learned after launch that hints are used to build these tests on mobile platforms… So, either you will get used to them or there will be no grammar hints in hints, unfortunately.
Anyway, they can be safely ignored, as they are never parts of the correct solution. ;)