First use case for these “da” words is stand-ins — simple
reference to an object that was mentioned before in the sentence or in
the previous sentence.
1.1. 1.1. Examples
Ich träume davon. (der Party)
Ich denke daran. (meinen Termin)
Ich freue mich darauf. (das Festival)
1.2. 1.2. Anti examples
“Da” words are only used when in reference to
non-living beings: e.g. people and animals are not subject to these “da”
words.
Ich habe mein Buch von ihr. (Maria)
Ich denke an ihn. (meinen Opa)
Ich spiele mit ihr. (der
Katze)
2. 2. Sentence conjunction
(Präpositionalobjekt)
Second use case for these “da” words is to connect two sentences. In
other words, the word that needs eine Präposition is replaced
with a sentence and the preposition serves the function of a conjunction
between these two sentences. This preposition is a pointer that
points to the next sentence.
The following examples clear any possible confusion about these
Präpositionalobjekten.
2.1. 2.1. Examples
Maria wartet darauf, dass der Bus
kommt.
Maria waits for the bus to come.
Ich freue mich darauf, von dir zu
hören.
I am looking forward to hearing from you.
Ich denke darüber nach, meinen Job zu
wechseln.
I am thinking about changing jobs.
Ich bin sauer darauf, dass mein Mitbewohner nie
saubermacht.
I am angry that my flatmate never cleans.
Here, the “dass” is represented by “that” in English,
however the “darauf” is still needed.