Wer, was can be used as relative pronouns and as interrogative pronouns. Examples:
Wen wir schicken ist gleichgültig. (Whom we dispatch does not matter.)
Wen schicken wir? (Whom shall we dispatch?)
The plural form is obtained by adding the fixed form alles at the end of the last pronoun. Examples:
Wer alles wird kommen?
Was gibt es alles zu sehen?
