I may have a better solution first.

[Karen Lewellen]

How much has voiceover changed since the last actually available outside 
of the system  users guide?
That would be likely high Sierra I believe?
If not a great deal then I could do  something quite practical, read in my 
main computer practicing over and over without needing to figure out what 
is being said at the same time.
I have the guide  for high sierra, one of my stateside associates, who is 
not upgrading her mac, wants to learn as her vision becomes more 
challenging.
Kare