A phrase from a movie is
Der Wald ist die Urheimat dieses kleinen Kobolds.
Kobolds is Genitive case, there is an s at the end. The same for dieses. But why is it kleinen and not kleines?
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Sign up to join this communityA phrase from a movie is
Der Wald ist die Urheimat dieses kleinen Kobolds.
Kobolds is Genitive case, there is an s at the end. The same for dieses. But why is it kleinen and not kleines?
If you are following some kind of rule that the adjective carries the ending of the determiner when no determiner (or a determiner with no ending) is present, you've hit on the one exception to that rule.
dieses selbstgebackene Brot
(ein) selbstgebackenes Brot
mit einer großen Anstrengung
mit (welch) großer Anstrengung
But in the genitive singular masculine and neuter, the adjective has -n, whereas determiners have -s (with some exceptions).
der Geruch des gerösteten Kaffees
der Geruch gerösteten Kaffees
That is because the adjective declination rules in German are somewhat complex. In short, as soon you have one strong ending on a determiner, the other possible places to put the strong ending get weak.
In your example, dies has the strong ending, and that means klein gets a weak ending.
Here's an explanation and a recipe.
If you follow that recipe, you will see that question #1 Is there an article is answered yes, and question #2 Is article in original form is answered no, which leads to the -en adjective ending.
Most of the time, it boils down to those two questions so practice that a lot. After a while, you don't have to think about it any more. Go on with practising the other two questions then.