In impress how to create a master slide for a title only type of slide

I need to create several master slides : one for each type of slide : title only, title and content and so on.
Each master slide I create is a standard master slide with a title and a content containing a hierarch of 6 bullets.
Whenever I try to delete the content it refuses.
When in master slide I have no access to the type of slide.
So how to do it?

Hello,

read Impress - Guide 7.0, Creating master slides, page 39 f.

Hello. Thank you for your answer. I read in detail Impress guide 7.0. Unfortunaltely, it does not work like explained in point 5 of the guide
After creating a new master slide and renaming it, the new master slide has the default content. That is a title and a standard content… If I try to delete these elements, I get an error message.
" this function cannot be executed with the selected object"

If I create new elements in the master slide, the new elements super impose on the standard elements.
In other words I can nver get rid of the title and the default content.

Any help would be welcomed.

Otherwise you can look here:

My Master Slide in Impress