Impress document with both landscape and portrait slides

I am a newbie using LibreOffice and its products.
I would like to make an Impress slide show that contains a mix of landscape and portrait oriented slides.
Any ideas on how can I do this, please?
It seems that I can have ALL landscape or ALL portrait, but I am unable to work out how to have a mix. Any ideas gratefully appreciated. Thanks.

There’s no such functionality for Impress. It is assumed that when you are presenting slides, the media (e.g., screen) has the same dimensions for all slides. If you are creating “slides” that would be e.g. printed, then you should use Writer instead.