Questions & Answers about Die Vortragende bittet uns, leise zu bleiben.
Because Vortragende is being used as a noun here, not just as an adjective or participle.
German often turns adjective-like words into nouns this way:
- der Vortragende = the male presenter/speaker
- die Vortragende = the female presenter/speaker
- die Vortragenden = the presenters/speakers
When an adjective or participle is used as a noun, it is capitalized in German.
It is a substantivized participle/adjective.
It comes from the verb vortragen = to present, give a talk, deliver a lecture/presentation.
So vortragend originally means something like presenting. When German turns that into a noun-like form, it becomes:
- der Vortragende
- die Vortragende
So grammatically, it behaves like an adjective with adjective endings, but functionally it means the presenter / the speaker.