Breakdown of Ich habe dem Kunden geantwortet.
ich
I
haben
to have
antworten
to answer
der
who, which, that (relative pronoun; die, das)
Questions & Answers about Ich habe dem Kunden geantwortet.
Why is it Kunden if there is only one customer?
Kunde is a weak masculine noun that follows the N-declension rule. This means it adds an -n or -en to the end in every case except the nominative (when it is the subject). Because it is the dative object here, der Kunde becomes dem Kunden.
Why do we use the dative dem Kunden instead of the accusative den Kunden?
The verb antworten (to answer) is a special verb that always requires the dative case for the person receiving the answer. Even though the customer feels like a direct object in English, German grammar treats it as answering to someone.
Why does the past participle geantwortet end in -et instead of just -t?
Regular past participles usually end in just -t (like gespielt or gemacht). However, because the stem of antworten already ends in a -t (antwort-), we add an extra -e- before the ending to make it easier to pronounce.
Why is geantwortet at the very end of the sentence?
In the German present perfect tense, the conjugated helping verb (in this case, habe) takes the second position in the sentence, while the past participle (geantwortet) gets pushed all the way to the end.