This is the 15598th most frequent German word.
wen
"Whom" (accusative form of "wer," meaning "who").
The word 'wen' is used here as the accusative interrogative pronoun to inquire about the direct object of the action 'hast gesehen'.
Wen hast du gestern im Park gesehen?
Who did you see in the park yesterday?
The word 'wen' is applied as the accusative form of 'wer' ('who') to denote the potential direct object of the action 'fragen'.
Ich weiß nicht, wen ich noch fragen soll.
I don't know who I should ask.
In this sentence, 'wen' identifies the person sought by 'Ihre Kinder,' serving as the direct object of the verb 'suchen'.