[Yonsu]

I don't know if you're already cool with this, but the way I like to think about kore/sore/are/etc.etc.etc. is this way:
Prefix ko = this
Prefix so = that
Prefix a = that over there

Suffix ko = implies location
Suffix re = implies object
Suffix no (like in "kono tsukue") = used when replacing 'ko' with a noun.

And I don't know how to explain this clearly, but prefix 'do' implies a question. Like KOno hito means this person. But DOno hito means which person. I like to think that the do prefix functions as the equivalent of the WH interrogative words (is that what they're called?).

With 'na' adjectives, you use the 'na' when it comes before the noun it's describing. For example, 'clean desk' would be 'kirei NA heya'. But if you say 'this desk is clean' it would be 'Kono heya wa kirei desu'.

Please correct me if I'm wrong.