Batch File Partial Renaming Example?

I am failing to understand what is likely a simple example, but could someone please provide an example or screenshot of the syntax to bulk, partially rename, a series of pdf documents:

from:

Jeans Musical News Newsletter-1983-06.pdf
Jeans Musical News Newsletter-1983-07.pdf

to:

Periodicals_Hobby_Jeans_1983-06.pdf
Periodicals_Hobby_Jeans_1983-07.pdf

Thanks for any guidance.

New name: Periodicals_Hobby_<Substr:1:" "><RSubstr:1:8>

Reply to #2:


Thank you