[FOM] Classification theory of abstract elementary classes by Shelah

[pax0 at seznam.cz]

 I'm trying now to decode the 2-letter abbreviations on pages 72,73 in the Shelah book.
 The only  which google didn't find are
 qr
 vq
 bu
 qt
 mat
 Does someone know what they stand for?
 It is better to have some mnemotechnic when reading.
Thank you,
Jan Pax