E-mail rules examples

1

is there a template to move e-mails to junk if there is no subject,

2

Unfortunately there is no argument to search for an empty subject. Sorry.

But you should check with your email provider. The may have filters that can do that.

3

could I vary the request for rule so that rejection occurs
if not starting with letters ‘a’ or ‘b’ or ‘c’ …(etc) { ignore case}

so that I could test it/improve

thanks