Understanding grammar will help you on your way to foreign language fluency. In the German language, adverbs, as in English, do not take declensional endings; they keep the same form no matter how they are used in the sentence. Certain words are always adverbs:
|jetzt —||now||da/dort —||there|
|nie —||never||bald —||soon|
|nur —||only||hier —||here|
You will find these and others in any dictionary. Other adverbs, however, are formed from adjectives. Their ordinary or positive form is the same as the adjective itself, but completely without declensional ending:
The demonstrative adjective to indicate something relatively near (this, sing.; these, pl.) also has several forms in German: dieser (m.), diese (f.), dieses (n.), diese (pl.).
Not only do they have to agree in gender and number with the noun they replace or modify, they also have to decline for case.
|Dieser Mann ist wirklich groß.
This man is really tall.
lch sehe diesen Mann oft am Bahnhof.
I often see this man at the station.
Geben Sie diesem Mann kein Bier mehr!
Don’t give any more beer to this man!
To signal something farther away (that, those), the forms are: jener, jene, jenes, jene. They also decline like the definite article.
Dieser Mann ist mein Großvater und jener Mann unser Nachbar.This man is my grandfather and that man our neighbor.
However, these days, it is far more common to use the definite article (der, die, das, die), stressed as a demonstrative adjective. So, in everyday German the above would turn into:
Der Mann (da) ist mein Großvater und der Mann (dort) unser Nachbar.